Robby1870 Posted July 9, 2007 Report Share Posted July 9, 2007 This has been happening off and on for a little while now, but today it was a lot worse. Starting it cold is rather rough, especially today I smelled unburnt fuel. Also, warm, in gear idle is kinda rough and voltage overall seems a little low (read: new alternator). The warmer the car gets the lower the voltage. It keeps its head above water, but not by much. Anyway, all of this has lead me to think either ICM/coilpacks or crank sensor. I have a spare set of ICM/coilpacks so that's easy. I just wanted any other input/suggestions before I started fixing things. I guess it's a good thing I have a second vehicle now. Quote Link to comment Share on other sites More sharing options...
Brian P Posted July 9, 2007 Report Share Posted July 9, 2007 if you have the spare coil pack, definetly try it. If not, then start pulling plugs and check for any soaked ones, fouled ones, then check compression. How low does the voltage get? Just before the crank sensor went on my old Cutlass, it had a hard start when warm (which is next to impossible on a 3.1, it almost always fires quick when warm) then the next day it would not fire at all. Quote Link to comment Share on other sites More sharing options...
Robby1870 Posted July 9, 2007 Author Report Share Posted July 9, 2007 When warm, the voltage sits around 13.2-13.5, even lower when the fans kick on (60v6 chip so they kick on early). My only explanation for this (and it's kinda far fetched) is that the ICM/coilpacks are drawing more from the alternator? I'm not even sure if that makes sense, but it's a thought. Also, battery is 1 year old. I don't think it's compression related because once it fires up, its fine, just idles kinda low and rough. Plugs and wires are 2 years old, fuel pump is 1 year old, alternator is less than a month old. Only thing ignition related I haven't replaced is ICM/coilpacks. Today, it was sorta warm (went to bank during lunch) and it kinda hard started then, but nothing major. I'll do ICM and coilpacks and see how that goes, then I'll do crank sensor if that doesn't solve it. Like I said, when it's actually moving it runs fine, no misses or anything, voltage still sits kinda low when running, however. Quote Link to comment Share on other sites More sharing options...
Brian P Posted July 10, 2007 Report Share Posted July 10, 2007 if you're above 13V at idle I think you're ok, at least for the short term. keep us posted. Quote Link to comment Share on other sites More sharing options...
slick Posted July 10, 2007 Report Share Posted July 10, 2007 Do you have a spare alternator to throw on just to test? Quote Link to comment Share on other sites More sharing options...
Robby1870 Posted July 10, 2007 Author Report Share Posted July 10, 2007 Do you have a spare alternator to throw on just to test? I replaced the old alternator with a new one because I thought this low voltage issue (worse, the warmer it gets) was the alternator getting heat soaked. But, this new one acts EXACTLY like the old one. I may have to hold up replacing the coil packs as it's supposed to rain later on. Instead I'll clean on the Toyota some. Quote Link to comment Share on other sites More sharing options...
19Cutlass94 Posted July 10, 2007 Report Share Posted July 10, 2007 All alternators will do this. Its the same way with every car/ignition system. Warmer it gets the lower the voltage. Colder it get thes higher the voltage. You said your voltage is like 13.3v.... now in the winter time check it again. It WILL be in the 14.0+v range. Anything above 13.0v is fine and wont cause any problems. It seems to me that you have an IGNITION problem not and ELECTRICAL problem. Quote Link to comment Share on other sites More sharing options...
Robby1870 Posted July 10, 2007 Author Report Share Posted July 10, 2007 All alternators will do this. Its the same way with every car/ignition system. Warmer it gets the lower the voltage. Colder it get thes higher the voltage. You said your voltage is like 13.3v.... now in the winter time check it again. It WILL be in the 14.0+v range. Anything above 13.0v is fine and wont cause any problems. It seems to me that you have an IGNITION problem not and ELECTRICAL problem. I definitely think its ignition related too. I know the hotter it gets the lower voltage, but this car, last summer never got this bad. Anyway, yeah, it's ignition related it just kinda popped up the same time the low voltage thing did so I was trying to relate the two. Quote Link to comment Share on other sites More sharing options...
19Cutlass94 Posted July 10, 2007 Report Share Posted July 10, 2007 This summer is worse than last summer though... Quote Link to comment Share on other sites More sharing options...
Brian P Posted July 10, 2007 Report Share Posted July 10, 2007 This summer is worse than last summer though... Yeah Rob I'm gonna vote normal too, even though it didn't seem that way last summer. Are you going by just the gauge, or a multimeter? Quote Link to comment Share on other sites More sharing options...
Robby1870 Posted July 10, 2007 Author Report Share Posted July 10, 2007 This summer is worse than last summer though... Yeah Rob I'm gonna vote normal too, even though it didn't seem that way last summer. Are you going by just the gauge, or a multimeter? Gauge.....guess I shouldnt worry about the voltage. Quote Link to comment Share on other sites More sharing options...
Robby1870 Posted July 11, 2007 Author Report Share Posted July 11, 2007 Okay I swapped out the ICM and coilpacks with a spare set I had. I will note here that I do not know for a fact that the spare set is good, but when I bought it the guy said it came off a running car and was working fine. Now to the problems. I got it all hooked back up and I go to start it. Starts fine, tach goes up like it should, but then it immediately shuts off. Not a "a few cylinders miss then it shuts off", a complete shut off, everytime (tried it like 6 times). I checked both, IGN fuses, the DIS fuse, the ECM fuses and they all look fine. Basically, it starts fine, run for maybe a second after I turn the key back to ON from START, then dies. Also, no misses or anything on starting. Ideas? Maybe crank sensor? I guess I don't know when the ECM takes over spark after start up. I thought the ICM controlled spark during start up, then the ECM took over. Does the ICM use the crank sensor or only the ECM? Also, I might try throwing the old ICM/coilpacks back on tomorrow and see how it acts. My other thought is that the crank sensor wires is grounding out to the block or somewhere. I've had that happen before and it was a bitch to diagnose. I wanna leave the crank sensor as the last thing and rule out all other possibilities because the crank sensor is a much worse job than coil packs. Quote Link to comment Share on other sites More sharing options...
Brian P Posted July 12, 2007 Report Share Posted July 12, 2007 MAP sensor maybe? It's so hard to tell without a scan tool to read the data. But I can tell you that if the crank sensor is bad, it won't fire at all (first hand experience) Quote Link to comment Share on other sites More sharing options...
Robby1870 Posted July 12, 2007 Author Report Share Posted July 12, 2007 MAP sensor maybe? It's so hard to tell without a scan tool to read the data. But I can tell you that if the crank sensor is bad, it won't fire at all (first hand experience) When I broke a vacuum line on the MAP sensor it still started, but I guess that's not the same as it actually being broken. MAP would throw a code though, right? Quote Link to comment Share on other sites More sharing options...
slick Posted July 12, 2007 Report Share Posted July 12, 2007 MAP may throw a code, but not always. Generally isn't the MAP code like "Low Voltage" or something stupid like that? If you have a spare one, it's worth a shot to try it out. That, or pocket one at a JY. Quote Link to comment Share on other sites More sharing options...
Robby1870 Posted July 12, 2007 Author Report Share Posted July 12, 2007 I just got back from work and checked it for codes......nothing, just flashed "12" at me. But, I dont know if it was running long enough for the ECM to even know something is wrong. Still not sure what this is. MAP kinda makes sense and it makes more sense with the super rich start the other day. I just don't wanna go throwing money at stuff because right now I'm basically guessing. Quote Link to comment Share on other sites More sharing options...
slick Posted July 12, 2007 Report Share Posted July 12, 2007 I'd still find someone that has a spare map and swap before you would purchase new, or throw parts at it. Quote Link to comment Share on other sites More sharing options...
Robby1870 Posted July 12, 2007 Author Report Share Posted July 12, 2007 I'd still find someone that has a spare map and swap before you would purchase new, or throw parts at it. Yeah, dad's gonna send me a spare from home. While searching I found some posts that said Advance can test MAP sensors. I may go ask them. I might ask them too that if I buy a new MAP install it, and it doesn't fix the problem if I can take it back. Quote Link to comment Share on other sites More sharing options...
slick Posted July 12, 2007 Report Share Posted July 12, 2007 Definately worth asking before you blow your money. I know i'm always sure to ask on parts about them fixing the problem or not. Quote Link to comment Share on other sites More sharing options...
Robby1870 Posted July 14, 2007 Author Report Share Posted July 14, 2007 Put the old ICM/coilpacks back on and it runs fine. Go figure. Quote Link to comment Share on other sites More sharing options...
timestalker45 Posted July 14, 2007 Report Share Posted July 14, 2007 the coil packs are located on the bottom of ur car correct? if so then probable dirt, water got on the contacks making bad spark, use a sealent on the points to prevent that from happening.also have u tried cleaning injectors if there dirty then duh starting would be a b*tch dirty or pluged injectors could cause a lot of probs and through no check engine light, and as soon as its warmed it will start fine do to all the dirt being pushed out for that short time it run when ur useing it Quote Link to comment Share on other sites More sharing options...
Robby1870 Posted July 14, 2007 Author Report Share Posted July 14, 2007 Na, there was no dirt or water (hasn't rained in weeks) and the injectors are fine. What I concluded the issue was starter related. I put a thin shim in there (there were no shims) because I would get some binding issues on a cold start. Now, there are no binding issues and it starts fine. Quote Link to comment Share on other sites More sharing options...
timestalker45 Posted July 14, 2007 Report Share Posted July 14, 2007 oh ok well i wasnt sure if it was binding i didnt c that in ur description i thought it was just turning but not fireing. im gald to here u got it though mand i remeber my old buik 1980 skylark man i hated that car but the power u got from the carberator but it started giving me trouble starting and running turned out my flyleaf had nearly came off do to the bolts falling out. lol glad its all working now Quote Link to comment Share on other sites More sharing options...
19Cutlass94 Posted July 15, 2007 Report Share Posted July 15, 2007 Good to hear its working good again Quote Link to comment Share on other sites More sharing options...
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