hard to start or wont start when cold

[Oceandaemom]

When I first got my 89 a few days ago I noticed it was very hard to start when it was a cold engine and the outside temp is cold (around 30 f). It cranked just fine but would sputter and refuse to fire off before several tries. Once it fires up it shutters at idle until the engine warms up then it smooths out.

 

This morning it was 12 degrees and it just flat out refused to fire after many many tries. I pulled a plug out to look at it was soaked in fuel. I figured poor or no spark so I put a bulb type spark tester in line with one of the plugs and when I cranked it the light flashed although maybe a bit dim. All 6 plugs tested the same. 

 

I tried to start it again a couple hours later with an outside temp of 25 and after a lot of tries it fired up. It stuttered a lot but after warming up it smoothed out. Once it was at operating temp I turned it off and tried to start it again. It started instantly without issue.

 

Any suggestions on what my next step should be?

[Ronnie]

Did you check to see if all 6 plugs were wet with fuel? . The next time it won't start press the accelerator pedal all the way to the floor and hold it there while cranking. That should tell the ECM the engine is flooded and stop fuel enrichment. Let us know what happens.

 

Since you seem to have a decent spark, the next step for me would be to connect a fuel pressure tester to the fuel rail when it won't start to make sure the fuel pressure is within range - above 35 psi is should start. If the reading is really high the fuel pressure regulator might be bad causing it to flood. Fuel Pressure Testing instructions

[Oceandaemom]

I tried starting it up just now when I got home and it started up after a couple seconds of cranking, although it is still about 25 degrees out so I will try again tomorrow morning when its in the 10-15 range again.

 

I didn't pull out all 6 plugs but I did pull out the three on the bank closer to the front of the car (because they were easier to get to). All three were very wet with fuel although that is likely just because I had been cranking it for a while without actually lighting it off. I tried the so called clear flood mode (holding the gas pedal down) this morning when it was acting up and it didn't have any effect. I am also going to try and find a better spark tester because the one I have doesn't really tell me a whole lot other then it is kind of doing something.

[Ronnie]

You really need a good spark tester. You need to know for sure it is getting a good spark before trying to troubleshoot the fuel system. I'm thinking it is getting a weak or no spark when it won't start. Since it is spraying fuel the crank sensor is probably good. Have you checked to see if there is gray goo on the side of the Ignition Control Module like you see in the photo below? That is a sure sign the ICM is bad.

 

[Oceandaemom]

I am afraid to say that like any good fault, this one is playing very hard to get. I picked up a better spark tester along with a fuel pressure tester in hopes that it would act up again and let me do some additional testing. Sadly, it has started without issue so far. Part of this may be that the temperature is now in the 40 degree range outside and the issue only presented its self when the temp was under 20 degrees.

 

I will report back if the temperature drops down enough to make it act up again.