LQ1 1993 stall, voltage, low MPG issues

[Arkin]

fine, people, looks like LQ1 is running.

http://www.w-body.com/showthread.php/80785-1993-LQ1-gt-L27

 

though there are still some serious issues, I'll appreciate any help and ideas

 

1) the engine works smooth on idle, starts good and 10 out of 10, thought the accessory belt is whistling all the way it works. belt, pulleys and tensioner are new ot just fine. also looks like I have a generator issue - the voltmeter hand shows OK after 1500 rpms, but if below I got insufficient volts. does it sound like I need to check the alternator bearing at least?

 

2) the engine works and sounds just fine, smooth and quiet. no stalls on the move. but if standing on the red light and trying to hit the gas as usual on a green one - the car stalls. it stalls nice and quiet just like if I turned the ignition off. to avoid stalling have to push the pedal really gently. I know that a fuel pump, filter and injectors were changed by previous owner, though don't know anything about the model of a pump. Also there were some issues with fuel line between cap and tank that had to be fixed. What do you think? Can be linked to numer 1) problem with voltage?

 

3) Extremely low MPGs. I guess 10 or so. I smell gas for some seconds after adding 8 gallons of fuel, but no bad smells except the light constant coolant smell under the hood and inside the car. The TPS and CPS were removed and intalled at least once in the past three months and were not calibrated. Check light somethimes is on, sometimes off, anyway I got EGR removed but the holes are still not jammed. Right, there are many things to check, but for now the main clue to think about are other problems listed above that may participate.

 

here are the actions I'm gonna perform tomorrow:

 

- check the fuel lines

- check the coil packs

- check the CPS to be sure it is clean

- check the TPS, clean the throttle and idle valve

- check the codes with paper clip

- finally block the EGR

 

here are some picks to keep you interested

Edited February 2, 2015 by Arkin

[Galaxie500XL]

Could be a bad throttle position sensor causing the stalls, a scantool would be very useful. In my experience often poor fuel mileage can be an O2 sensor on it's way out---they'll often give poor performance long before a check engine light comes on.

[rich_e777]

Nice pics, I love those Z34 models. Its hard to imagine an engine running nice and smooth but only getting about half the MPGs. Have you changed the spark plugs and wires already? I get everyones car mixed up sometimes so I cannot recall if you mentioned you've done this already. If all other inspection come up with no clues then I`d start suspecting the O2 sensor or the EGR valve, EGR valve is cleanable but it will only do good for so long until it need replacing as well.

 

I replaced mine after feeling like a good project and It did make my 3100 run a lot better, then the Saar man instilled paranoia because it was a Bosch brand O2 sensor.

[Arkin]

I changed plugs, but the wires are old. One of the wires is bad for sure, I'll try out with the wires from camaro, maybe will help a bit

 

What if I won't instal EGR at all any more? I'm gonna just weld the holes. Right, I will have a permanent check engine, but I'm sure there is a way out. I drive successfully 2001 firebird with EGR taken off, and holes welded.

 

Same thing for catalytic converter. If I will rip it out (maybe it's already absent- I will check) and not instal anymore, do I need to bother about O2 sensor? Should I keep it working and what are the consequences? My pontiac is also without converters, though I don't know if O2 sensor do the job there.

Edited February 2, 2015 by Arkin

[Galaxie500XL]

The O2 sensor is vital to the ECM making proper fuel delivery decisions to the engine. Typically, as they age, they get "lazy", and report to the ECM that the mixture is lean, and enrich the mixture. In the case of your car, it's unlikely a rich mixture is doing much of anything to the catalytic converter, it likely quit doing much years ago, but I'd recommend against removing it--unless it's plugged up, and causing a restriction in exhaust flow, it's not really hurting anything, and if later emissions testing comes to your area, a missing converter will most likely result in an automatic fail.

 

As far as the EGR, I see very little benefit in a stock engine in welding the passages shut, and if I recall correctly, you'll need to modify the ECM programming to prevent the check engine light from coming on, once the ECM notices the EGR is missing.

I changed plugs, but the wires are old. One of the wires is bad for sure, I'll try out with the wires from camaro, maybe will help a bit

 

What if I won't instal EGR at all any more? I'm gonna just weld the holes. Right, I will have a permanent check engine, but I'm sure there is a way out. I drive successfully 2001 firebird with EGR taken off, and holes welded.

 

Same thing for catalytic converter. If I will rip it out (maybe it's already absent- I will check) and not instal anymore, do I need to bother about O2 sensor? Should I keep it working and what are the consequences? My pontiac is also without converters, though I don't know if O2 sensor do the job there.

Edited February 2, 2015 by Galaxie500XL

[Schurkey]

The FIRST thing you do is to verify--and repair as needed--the low-voltage condition.

 

Nothing else in the vehicle's computer control or fuel systems can be trusted until the voltage everywhere in the vehicle is proper.

 

 

 

 

 

 

 

If you don't understand what an EGR valve, catalytic converter, or O2 sensor does, maybe you shouldn't rip them out just yet.

Edited February 2, 2015 by Schurkey

[Garrett Powered]

sounds like the engine ground strap to the body is needing replaced and how old is the battery? could be that the alternator has the high output stator that doesn't charge at idle or bad regulator if you fix the other problems and it still comes back. or it just needs a drivability tune flashed to it.  for now keep all the accessories off at the stop lights. <br><br>if it does need a tune you can fix it, fix it, and fix it some more. still needs the throttle follower table tweeked or it will still feel like that as you take off from a light. what gas you running? deathanol?

[Nas Escobar]

Considering I've had a similar issue (and bad LIMG to boot), these would be the things I would do in order...

 

1. Remove alternator and have it tested. (bitch to do, yes I know; removing strut and lower control arm helps to clear space. Axle does have to come out)

2. Check clip at the back of the alternator for any shorts. A peeled cable will hit the metal and short out, thus causing the ECM to read a voltage f 11.5 to 10.9. In my case both the cable was peeled and the alternator had a bad regulator. I caught on to the bad regulator when I noticed that if I revved the car to 4000rpm and held it there for 15 seconds, I would get back 14 volts.

3. If everything checks out, check all major positive and negative cables and then verify there are no shorts nor corrosion. This would also mean that you would need to service your terminals and make sure there's no corrosion there. Corroded terminals make for bad connections.

 

As far as the 10mpg goes, put back the EGR (those can be cleaned if they're sticking or otherwise acting bad), and make sure there's no vacuum leaks. The LQ1 is very picky about this. One leak and the engine goes to shit. I had mine die a couple times because I lost the screws to the vacuum on the passenger's side of the intake plenum and it would pop off.

 

Make sure all plugs aren't fouled and check for deposits. Get new spark plugs if they are bad (Fouled, white deposits are a sign of combustion) and get new plug wires. Replace all 6. If you can get your hands on an ALDL cable and a laptop, please do. There's a program called TunerPro and you should be able to use it as a Tech Scanner. This means you'll be able to see the major things that you would need to know about how your engine runs at idle and during load. If you find the engine has a specific load and fuel %, you have a misfire. The program can also tell you which cylinder is misfiring and you can either do a compression test or swap out the coil.

 

The coils on these cars do go bad after a while so if you replace one it should give you back some pep. That was the case with mine.

 

The basic take home points are these... Check to make sure there are no vacuum leaks... put back the EGR. You can take off the catalytic converter as OBD1 doesn't check its function. 1993 had the o2 sensor before the cat and deleting the o2 will make the car run rich. Don't delete the o2 or the EGR without a computer tune. Don't remove the MAF either. Check the PCV valve to make sure it works. If it makes noise, it's bad and needs to be swapped.

 

Forgot to mention, but check your MAF for proper function, clean it and clean the IAC that's on the intake tube as well.

 

Also, have you verified there is no LIMG leak? The LQ1 has a plastic gasket that does fail, and one of the symptoms is a stalling engine. Mine used to die when I had a cold start and had a very weird idle. Spray carb cleaner on the edges of the LIMG (does require the injector cover to be off) and see if it does anything. If the engine surges, that's bad. If the engine does nothing, you're ok..

[55trucker]

Where you are in Europe can you get parts easily?

 

The alternator problem sounds to me like the rectifier pack has a bad diode, low voltage output at idle (or near idle) get the engine rpm's up and the voltage begins to return (a simple test you can check with a voltmeter). The diodes can be replaced, but it's not a job to do if you don't have the proper tools to get the C130 apart, the stator terminals are soldered in place with silver solder (torch is needed to get them free).

 

On the accessory belt....is this by chance a Goodyear Gatorback belt? , they are prone to squealing, went thru 3 of them, all new ones, got rid of it, went to a Gates or Dayco belt, squeal gone.

 

The stalling issue *might * be low voltage related, get the alternator sorted out, revisit the stalling problem.

 

Gas smell?,

 

at the back near the tank? have a close look at the vapor canister lines, the canister is located behind the left rear wheel tucked up behind a plastic shield in the wheel housing, the vapor lines do rot out if not protected, if any of the pipes & in particular the pipe going forward up to the purge solenoid (mounted on the top of the engine intake plenum at the back, at the forward end of the plenum next to the firewall) is opened up then the purge solenoid can't do it's job properly and it will allow air to be sucked into the engine causing a lean situation when the solenoid opens.

 

Don't bypass the EGR, it is necessary for proper engine cylinder temp control, without it the cylinder temps can rise to an abnormal level, and as you are experiencing, stalling/poor fuel mileage.

[Psych0matt]

 

Forgot to mention, but check your MAF for proper function, clean it and clean the IAC that's on the intake tube as well.

 

wouldnt being a 93 it'd be a speed density car, right?

[94 olds vert]

wouldnt being a 93 it'd be a speed density car, right?

 

Right

[Nas Escobar]

wouldnt being a 93 it'd be a speed density car, right?

 

I'm not very familiar with the 91-93 LQ1's, I only suggested it because I know most cars have issues with stalling and MPG when the MAF is going out.

[Arkin]

wow many thanx to you men, I appreciate so much involvement in my issues. I love the US stuff, I drive only US cars and Lumina is for sure worth of pain in the ass for a while

as for the gas. the best way to spoil your engine - fuel it on Ukrainian or Russian gas stations. there is no choice of leaded\unleaded fuel. all fuel stated as unleaded but you never know for sure. the gas here is a piss, contains much sulfur, lead and water. Ukraine doesn't have its oil, Russia got much oil but got awful oil products. so EGR and catalysts die first and usually are never cared about anymore. there are no laws to obligate people care about emission, mostly because there is an extremely large number of carb engines without catalyst at all. I know that sounds wild. Anyway all three other US cars I drive got no EGR or got a EGR check light and that doesn't affect much on MPG or performance. As for the cats, removing burnt ones increase exhaust performance and that's another reason not to pay 200$ to reinstall it (god, how cheap are cats for lumina compared to other modern cars).

 

ok know as for my research. I've read the trouble codes. The self-diagnostic is a cool feature. So we have here 23 44 54 and EGR issues

23 - IAT voltage high\low

44 - O2 voltage high\low

54 - fuel pump voltage low

 

yes, my plan is to deal with voltage issues first. wiring is good so all things are up to alternator and\or voltage regulator. I've read much about that regulator, many people state not to serve generator but deal with regulator first since it's cheap and can be changed without opening alternator. my question for now is :

 

is it possible to change the regulator without removing all the stuff needed to get the alternator off the car?

can I change the regulator using others I can find on the market (from other cars etc)?

and finally if I buy a new alternator on rockauto, does the regulator come with it?

 

the other thing I will care is the fuel pump. I know it's not original, I guess it's not even compatible. So I plan to install the bosch high pressure pump. after that I will read the codes again and if there are still codes for sensors I will change them too.

 

by the way if its all OK with voltage and if I get no more trouble codes for sensors, does it mean they're good? I think it's hard and expansive to check the sensors, so if the self-diagnostic is capable with that - cool!

 

I buy parts from rockauto. So parts are no problem. Both time and money are the problem. If I deside to get generator, I have to wait 3 weeks, install it and if the problem is still there - I'll have to order the sensors and wait again.

 

My firebird and stealth to keep you interested<br><br><br><br>

[55trucker]

wow many thanx to you men, I appreciate so much involvement in my issues. I love the US stuff, I drive only US cars and Lumina is for sure worth of pain in the ass for a while

as for the gas. the best way to spoil your engine - fuel it on Ukrainian or Russian gas stations. there is no choice of leaded\unleaded fuel. all fuel stated as unleaded but you never know for sure. the gas here is a piss, contains much sulfur, lead and water. Ukraine doesn't have its oil, Russia got much oil but got awful oil products. so EGR and catalysts die first and usually are never cared about anymore. there are no laws to obligate people care about emission, mostly because there is an extremely large number of carb engines without catalyst at all. I know that sounds wild. Anyway all three other US cars I drive got no EGR or got a EGR check light and that doesn't affect much on MPG or performance. As for the cats, removing burnt ones increase exhaust performance and that's another reason not to pay 200$ to reinstall it (god, how cheap are cats for lumina compared to other modern cars).

 

ok know as for my research. I've read the trouble codes. The self-diagnostic is a cool feature. So we have here 23 44 54 and EGR issues

23 - IAT voltage high\low

44 - O2 voltage high\low

54 - fuel pump voltage low

 

yes, my plan is to deal with voltage issues first. wiring is good so all things are up to alternator and\or voltage regulator. I've read much about that regulator, many people state not to serve generator but deal with regulator first since it's cheap and can be changed without opening alternator. my question for now is :

 

is it possible to change the regulator without removing all the stuff needed to get the alternator off the car?

can I change the regulator using others I can find on the market (from other cars etc)?

and finally if I buy a new alternator on rockauto, does the regulator come with it?

 

the other thing I will care is the fuel pump. I know it's not original, I guess it's not even compatible. So I plan to install the bosch high pressure pump. after that I will read the codes again and if there are still codes for sensors I will change them too.

 

by the way if its all OK with voltage and if I get no more trouble codes for sensors, does it mean they're good? I think it's hard and expansive to check the sensors, so if the self-diagnostic is capable with that - cool!

 

I buy parts from rockauto. So parts are no problem. Both time and money are the problem. If I deside to get generator, I have to wait 3 weeks, install it and if the problem is still there - I'll have to order the sensors and wait again.

 

 

The alternator is a C130, the regulator is internal, the stator comes away from the front housing with the back housing, the stator is hard soldered to the terminals inside the rear housing casing, to get the stator free you have to heat the silver solder compound at the terminals (a regular soldering iron will not be hot enough) (do NOT cut the terminals, doing so will shorten them making it impossible to resolder them), once the stator is free you can pull it out of the casing,now you can see the regulator & the rectifier inside down at the bottom of the housing, they both come out from the top. Check the rectifier to see if there are any leaks, for simplicity sake just replace the entire rectifier pack. If all of this is too much work then order a complete replacement alternator, but before you get into all of this, do a simple test with a voltmeter with the engine running, if the voltage at idle (with no accessories on) is low (12v or even less) but the voltage comes up to 13.7+ when you raise the engine rpm that's an indication that the rectifier is bad.

 

Getting alternator off the DOHC is not the easiest job, it requires going in thru the passenger side wheelwell, removing the strut, the axleshaft, the splash shield, the axleshaft shield, etc etc.

 

Get the electrical sorted out first, then go after the codes.

 

 

 

http://alternatorparts.com/cs130-sbpage1.html

 

http://www.google.com/imgres?imgurl=http://alternatorparts.com/Exploded%252520Views/DR-CS130.jpg&imgrefurl=http://alternatorparts.com/xcs130.html&h=736&w=500&tbnid=wsM6li2e4ro2cM:&zoom=1&docid=k-VjZY6xaYQWtM&ei=JWzSVLi-FJb-yQTwx4HYCA&tbm=isch&client=palemoon&ved=0CB8QMygBMAE

Edited February 4, 2015 by 55trucker

[Schurkey]

If you're concerned about the rectifier, why not just test for AC output, and maximum DC output from the alternator?

 

If the diode(s) is shorted, you'll have excess AC on what should be DC output.

If the diode(s) is open, you'll have reduced DC output.

 

A proper ON-THE-CAR alternator/starter/battery test will pretty much reveal all things.

[Arkin]

for me, bad rectifier = bad alternator, the work is too complicated, so I'll prefer to get a new complete unit. thanx for info anyway, deep knowledge

but when I told about voltage regulator I meant this thing: 32$ on rockauto, I suppose it installed outside the alternator

[Schurkey]

for me, bad rectifier = bad alternator, the work is too complicated, so I'll prefer to get a new complete unit.

Not only understandable...very wise. I've never in my life opened-up a CS-style alternator. If it fails testing, I get another one.

 

thanx for info anyway, deep knowledge

So you can still test the rectifier, and replace the alternator if it's failed.

but when I told about voltage regulator I meant this thing: 32$ on rockauto, I suppose it installed outside the alternator

Nope, it goes inside...and I don't do "inside" a CS-style alternator.

[Garrett Powered]

the cs130d has an external regulator, cs130 is internal. I have had custom made both kinds with completely new internals. also upgraded to the cs130d on a few cars because you can go farther with that chassis on a build. but you need a special press to even remove the stator from the case properly. Is the ground from the block to the car body the original wire? I guarantee it will be bad if it is, knowing you already have issues.. I would be able to disprove many myths by watching datalogs on my computer of your car running. viewing all sensor data on graphs along with voltage. watching fans kick on and off at idle and seeing voltage surges. not only that I can fix it without ever getting my hands dirty.

[Schurkey]

the cs130d has an external regulator, cs130 is internal.

I'm thinking the voltage regulation of newer vehicles (new enough to have a 130D) is done by the body computer. Is that correct? Are ALL 130Ds externally-regulated?

 

I can fix it without ever getting my hands dirty.

Holy crap! I though I was the Oral Roberts of auto repair! I'm not worthy, I'm not worthy.

[Garrett Powered]

I'm thinking the voltage regulation of newer vehicles (new enough to have a 130D) is done by the body computer. Is that correct? Are ALL 130Ds externally-regulated?

 

 

Holy crap! I though I was the Oral Roberts of auto repair! I'm not worthy, I'm not worthy.

 

 

my granny is a fan of oral roberts and my dad says he is a religious nut or something. I am not sure who he is, but I know I would never give him money. what I meant is that my car was never going to run right without me fixing it in the tune.

 

It's like when you know how a song has bass but you cant hear it until you adjust the EQ. it doesnt mean the speaker is blown when you turn it up and it distorts, you just adjust the low end and get it to a spot where it sounds good at pretty much any volume. This is EXACTLY how it is done in this situation. only the IAC motor is the speaker. also there are other adjustments that you could say are similar to tuning in your stereo. like the idle speed tables the IAC steps can be adjusted to sort of regulate the voltage. but the regulator is a module that outputs voltage based on demand, not really what the tune says. unless you command more rpms or IAC steps which will help a lot. you cant really fix it with repair/replace though

[Schurkey]

Sure, RPM makes a difference...but if the alternator is actually defective, you can play with IAC steps until the cows come home. You're not going to fix anything until the alternator is replaced. (Note to original poster--your 3.4 engine uses a "special" alternator; and I've had experiences when the parts catalog illustration shows the correct alternator, but when I open the proper-part-numbered box...the alternator actually supplied doesn't have the correct case, and won't work. Be SURE of what you're buying to replace your alternator, if it comes to that.)

 

Same with cables/harnesses. No "tuner" adjustment will compensate for a corroded cable.

 

This is why I suggest an ON-THE-CAR starting/charging system diagnosis. Nothing beats looking at voltage, amperage, voltage drop between components--and--actual oscilloscope voltage and amperage waveforms, if a 'scope is available (not many folks have 'scopes.)

 

Until the voltage is correct, nothing else in the computer or fuel system is trustworthy.

 

 

 

 

 

 

 

 

 

 

 

As for the Oral Roberts reference, Ol' Oral was a faith healer, "laying hands" on the sick and praying for God to relieve their suffering. It's always a giggle to quietly fix some minor problem (plugging in a wayward vacuum hose, for example) while the vehicle owner isn't paying attention, then lay my hands on the fender and command the car to "Heal"! He turns the key and get the "purrs like a kitten" effect--and then his eyes get wide.

Edited February 5, 2015 by Schurkey

[Garrett Powered]

I agree, on everything, just how is it adjusted with a scope if a tune is needed?

[Arkin]

By the way there is one more thing. The exhaust smells like I've just started the engine with cold outside weather. Even after 10-15 minutes of iddling the exhaut smells like I just started it.

 

And a new portion of stupid questions.

 

1. Where I am able to find MAP sensor? The one connected into the air filter box is the IAT

2. I got a wire ending with nothing. It comes out of the common platic tube with wire for IAT sensor. I got no washer tank at all, I don't know where it is supposed to be, I bet that wire is for washer pump, right?

 

3. I got a wide connector just hanging there. Don't know what it is intended for though. I got no cruise control but I know cruise's connector has to be small

Edited February 5, 2015 by Arkin

[Garrett Powered]

yes that is the cruise plug, and unwrap the other to see what is going on. or just look at the datalog and see if it works.

 

 

also the lead in the gas should not stop you from using it. you could run it with the wideband sensor I use according to the manual. the lead is just a lube. also sulfer I heard is good for gas. I dont know how good it would be for big city use if everyone used it at rush hour, but you get the idea. still cleaner than coal.

[55trucker]

By the way there is one more thing. The exhaust smells like I've just started the engine with cold outside weather. Even after 10-15 minutes of iddling the exhaut smells like I just started it.

 

And a new portion of stupid questions.

 

1. Where I am able to find MAP sensor? The one connected into the air filter box is the IAT

2. I got a wire ending with nothing. It comes out of the common platic tube with wire for IAT sensor. I got no washer tank at all, I don't know where it is supposed to be, I bet that wire is for washer pump, right?

 

 

3. I got a wide connector just hanging there. Don't know what it is intended for though. I got no cruise control but I know cruise's connector has to be small

 

 

Correct on the cruise plug identification, the MAP is located on the top of the intake plenum, forward end of the engine, at the back near the firewall,

 

the washer tank should be sitting next to the battery & that taped off connector looks like it is the connector for the tank motor.

 

If you've got lead in your gasoline (benzene) I can understand why your getting an odour of sulphur often, lead will kill the o2 sensor which then will mess up your emissions & ruin the catalytic converter.