Okay, so just wanted to do an update while I'm waiting in the parts for the fuel filter pressure test. I had my icm tested yesterday, and it came back bad. But, the problem is the did it with the test for a blazer with vertical distributor towers instead of horizontal, does anyone know if this will skew the results?


Edit: got it tested the correct way today and my icm is bad, so by the end of the week we'll find out if that's what's causing my issues or not, I appreciate all the help and I'll post my results as soon as I pick a new one up

 

Don't put too much faith in those testers at the auto parts stores. I've seen, more than a couple of times, they connect it to the tester without using a heat sink to dissipate the heat from the module while testing it. As a result, the module burns up, they tell you it's bad, and sell you a new one. You can test the module very easily with a test light while it's still on the vehicle. Chances are, if the engine runs, the module is good. Occasionally you'll get one that acts up when it gets hot, but the engine will not run at all when that happens.

 

Okay, I talked to the only Chevy dealer near me today and he said that a crankshaft sensor relearn for a 95 is unheard of, so I'm not sure what to do there. Can you explain how I would go about testing the icm?

 

That's a problem that needs to be diagnosed and repaired.
Key ON, engine OFF, fuel pump running, fuel pressure needs to be 55psi to 61psi. It must remain above 50psi for at least 10 minutes after the pump shuts off. GM does not publish any "engine running" fuel pressure specs for this system.


1995 had two different fuel injection systems and three different computer control systems. Early production 1995 did not have a crankshaft position sensor. Mid 1995 and later are equipped a crankshaft position sensor. If you replaced it, the relearn needs to be done. You might need to look for another dealer. They typically don't appreciate it when the customer proves them wrong A good independent shop should have a scan tool capable of performing the relearn.


If the engine runs, it's very doubtful that the ignition control module is the issue. After the relearn, use the link in post #6 to diagnose the fuel delivery system. Post all 4 readings and we can analyze them. If we need to check the ignition module after doing the relearn and repairing the fuel delivery system, we can do that.

 

Okay, I'm getting the stuff for the fuel line tester this weekend, but in the mean time I'm going to be addressing my distributor issue and it got me wondering if that could be the issue I have at hand. My distributor cap can't screw on to my distributor due to the holes on my distributor being stripped. It doesn't seat perfectly and it wobbles quite a bit if I jiggle it by hand. Advance auto parts has a repair plate though, which is only $25 which is much cheaper than the couple hundred I was going to spend on a new distributor. While I'm doing this repair I'm going to take a look at the cap and rotor and see the condition of them, anything else I could do at this time to further investigate while I wait on my pressure tester adapter? Also just wanted to add in that I appreciate the help you're giving me more than you could ever imagine. This isn't exactly an easy time in my life and money is pretty tight, but I need to get this blazer running or its really going to be tight. I'm going to get that fuel filter tester on Friday and will test it then as well and when I do I'm going to put that repair plate on it.

 

I'm going to start a thread for my problem. It's similar to yours, but I don't want to confuse anyone that reads yours later. Captain Hook, you just gave me light. I hope you'll hop in on it.

 

Alrighty. I had a second mechanic look at it today and he said he's pretty positive it's the icm that's causing the problem. I'm going to pick on up on Friday. I'll post my results by Friday evening

 

Hmm, now there are three known problems: Fuel pressure leakdown is excessive, crank relearn needs to be done, and the distributor mounts. Save your money on the ignition module until you fix the known issues.


The cap & rotor are like bath water: you can't tell if it's good just by looking at it For the distributor, there are a few places online that have aluminum distributors, which are far better than the plastic OEM style. Skip White has an Ebay store and they're $50 shipped to your door. It comes with a cap & rotor, but you're better off using AC Delco.

 

Okay and just to add to the known problems, I have a bad output shafts seal in my transmission which has caused a little bit or transmission fluid in my vacuum lines, not very much and this again isn't part of my problem I believe, but that Is one of the more important things I'll fix that way I can verify that isn't the cause. I'll be testing the fuel pump and fixing my distributor problem tomorrow, so that knocks out two of the problems. I called a local shop today and they didn't know about the relearn either, really stumping me

 

Okay so I did a lot of work to the blazer this weekend, I got the fuel pressure leak down fixed, four fuel lines were leaking, got the code to go away by replacing the purge solenoid and I got the timing set correctly. Fuel pressure doesn't leak down anymore. I'm not entirely sure if it's fixed just yet, it wasn't earlier today, but I replaced a fuel line after that and ran it for a second and it felt fine. I'm going to test drive it tonight after work, and I'll post back with my resultsz