91 GP... Dead.

[Crazy K]

i want to say...

ICM or fuel injector.

 

got a multimeter? you can check two of the injectors without removing much of anything. do that and see what you get.

 

also:

check the vacuum line from the regulator for fuel

unplug the oxygen sensor and see what happens. if it runs ok with the check light on... it is probably bad.

 

[Addicted To Boost]

I just went back to pick my dad up and while I was there, I checked on the car..

 

It will not start now. It just cranks and smells VERY strongly of gas. I pulled the vacuum line on the FPR and no fuel came out, it seemed to be dry as well.

 

I do have a multimeter. I'll ohm out the injectors and see what I find.

 

I'm thinking maybe CKP sensor.. I'll have to check for spark as well. My buddy Kyle's TGP died EXACTLY like this, and still had spark, but the CKP sensor was bad and not giving the signal at the correct time.

[ManicMechanic]

My buddy Kyle's TGP died EXACTLY like this, and still had spark, but the CKP sensor was bad and not giving the signal at the correct time.

 

Same as my 1992 convertible had done.

[Crazy K]

that is possible too.

 

the CXP sensor is a "wear" part in my book. I pull all of mine and inspect, and once in a while I find a crack in an otherwise "good" sensor and replace it. TIP: coat the sensor completely in dielectric/silcone grease to protect it from oil and allow ease of removal if you ever had to pull it again.

 

even if the CXP fixes it, you could still have bad injectors. check it all.

[Addicted To Boost]

Thanks for the thoughts guys I'll see what I can get done tomorrow..err today.. man I need to get to bed..

[Dark Ride]

I'm thinking injectors sounds like how my old GP ran when they were bad.

[Night Fury]

X3 on teh injectors! thats why my CS PHAILED

[spiderw31]

My votes would be either O2, ICM, or injectors (not necessarily in that order though).

 

Someone correct me if I'm wrong here, but I believe that there is a "flood clear" mode that is activated when holding the throttle to the floor while cranking. I was told that if you did this, the injectors wouldn't pulse at all, and the point of it was to clear the cylinders in case the were flooded with fuel. If thats the case, it could help you in two ways. First, it could clear the flood condition and maybe allow the car to start, allowing further diagnosis. Second, if it did nothing and the car still reeks of gas, then obviously an injector is dumping fuel even when not commanded to.

 

Hope some of this is helpful and good luck!

 

P.S. - at least you're not slummin it in the Benz

[Crazy K]

I believe what spider says is correct.

[Dark Ride]

I believe what spider says is correct.

Really, I never knew that, thats good to know.

[Addicted To Boost]

there is a "flood clear" mode that is activated when holding the throttle to the floor while cranking. I was told that if you did this, the injectors wouldn't pulse at all, and the point of it was to clear the cylinders in case the were flooded with fuel. If thats the case, it could help you in two ways. First, it could clear the flood condition and maybe allow the car to start, allowing further diagnosis. Second, if it did nothing and the car still reeks of gas, then obviously an injector is dumping fuel even when not commanded to.

I tried that last night, and it would not start at all.

[Crazy K]

I believe what spider says is correct.

Really, I never knew that, thats good to know.

I think it is a throw back by design... that is also how you clear a flooded carburetor.

[Addicted To Boost]

I'm going to bring my multimeter and look into it more today and see what I can figure out. I'll replace the CKP since it is cheap, and could use replacement anyway.

[Addicted To Boost]

I went back and did a bit more investigating.. although it was getting dark out and raining (in AZ?!)

 

I ohmed the injector on the passenger side I could get to without taking the plenum off and it was at 12.2.

 

I turned the key on and let the fuel pump prime, then I went to the schrader valve on the fuel rail and pressed it.. no fuel came out.

 

I had someone else get in the car and turn the key, while I was pressing on the schrader valve.. and fuel sprayed out while the fuel pump primed. I also noticed that just below my intake plenum between the plenum and front valve cover, there is yellow discoloration (gas). I pulled off my intake hose and its dry in there, even after cranking it over.

 

The vacuum line going to the FPR is dry and in good shape, and the previous owner replaced the FPR and the fuel pump on it already.

 

I'm thinking I maybe have fuel injectors stuck open and dumping fuel into my engine... that fuel is going somewhere..

 

What do you guys think?

[Addicted To Boost]

bump

[spiderw31]

...I turned the key on and let the fuel pump prime, then I went to the schrader valve on the fuel rail and pressed it.. no fuel came out.

 

I'm thinking I maybe have fuel injectors stuck open and dumping fuel into my engine... that fuel is going somewhere..

 

What do you guys think?

 

Between this and not clearing the flood with the throttle in the floor while cranking, I'd say yeah it sounds like a stuck injector. Try pulling plugs and see which ones are soaked in gas, and you'll know which injector is open.

 

 

 

[RobertISaar]

...I turned the key on and let the fuel pump prime, then I went to the schrader valve on the fuel rail and pressed it.. no fuel came out.

 

I'm thinking I maybe have fuel injectors stuck open and dumping fuel into my engine... that fuel is going somewhere..

 

What do you guys think?

 

Between this and not clearing the flood with the throttle in the floor while cranking, I'd say yeah it sounds like a stuck injector. Try pulling plugs and see which ones are soaked in gas, and you'll know which injector is open.

 

 

 

 

yeah, that would be the simplest way to check...

[Addicted To Boost]

I pulled the injectors out and checked them for resistance.

 

12.4 12.3 12.2 12.1 12.1 12.0

 

What is the acceptable range for these injectors, and how can I tell if they are leaking?

[Crazy K]

I pulled the injectors out and checked them for resistance.

 

12.4 12.3 12.2 12.1 12.1 12.0

 

What is the acceptable range for these injectors, and how can I tell if they are leaking?

that is a decent range.

 

you can leak check them by installing them into the fuel rail only, and laying them on top of some paper in the engine valley, and manually operating the fuel pump to see if any leak out the bottom.

 

BTW... new injector O-rings are a MUST, and you should coat them with silcone/dielectric grease(or vasoline) before installing.

[Addicted To Boost]

Alright, I'll try that.

[Night Fury]

I just used motor oil on teh CS

[Addicted To Boost]

Alright I went back and plugged all the injectors back in, flipped the fuel rail upside down, and turned the key... ALL SIX injectors sprayed fuel everywhere! What would cause all 6 to go bad all at once? Or is this caused by something else? I have a video to show it happening as well.. I'll see if I can upload it.

[Addicted To Boost]

Video of the misbehaving fuel injectors

http://s80.photobucket.com/albums/j195/blackswift99/1991%20GP%20SE/?action=view&current=Video003.flv

[ManicMechanic]

For some reason, PB videos do not work here.

[jake91]

you have to do a direct link