TLS_Addict

Figured I would post in here since some of you have been following my issues in the For Sale thread.

I picked up a 1992 6 speed coupe off a member in here a few weeks ago. I knew it didn't run and the owner just wanted it gone. I can't blame him for all the issues it has given him.

First things first, I replaced the dead battery. What else did I find? Well, the computer rattled and I pulled the cover off the back and a Hypertec chip was installed but not fully pressed in. I also noticed the stock chip was inside rattling around. Took the hyperjunk out and replaced it with the stocker. I found a plug wire not connected and two other plug wires swapped! I jumped the pins and turned the key on and saw a single code, H74. Looks like from the radio replacement they fugged something up???

When I turned the key the fuel pump primes so I figured I would pull the jumper and try to fire it up. Low and behold it fired! It revved to about 1200 RPM and died. Hrm... With the paperwork in the folder the prior owner gave me I found that the fuel filter was changed some 13 years ago and 20k+ miles. I changed that and primed the system a few times and BAM! It fired and ran for about 10 seconds and died. It fires to about 1500 rpms and the idle had come down to about 900 and was smoothing out before it died. I tried to start it again to no avail. A tad of starting fluid saw the thing start again but died. I am not one to use a lot of starting fluid but it will run on it. Issue is this, if you try to modulate the throttle at all the pedal kicks back as if the ASR is activated. So while cranking it over I turned the ASR off and it fired up but died again within a moment. Each time oil pressure would shoot up to about 40-60, so I believe the sending hnit is functioning correctly. I also would say the relay is working for the fuel pump as it primes when you turn the key. It stays on for about 2-3 seconds each time. I did notice that once in a while after I try to start it the pump will reprime the system if I turn the key back to the "ON" position from the "Start" position. Other times it won't reprime. A few times I tried to see if the pump would prime the system 3 or 4 times in a row and a few times it wouldn't. Not sure if either of those are related to a bad pump or not.

Having searched, a lot, I have seen multiple issues that sort of fit this. As I ran out of time yesterday (I have a 4 month old) I will get back in the garage tonight and do a fuel pressure test. Also planning to test a NOID Light and check for pulsing, but my gut is that they are not.

As I am of the position that if it ain't broke don't fix it, I still am going to swap out some little things that cause issues. The car is reaching its golden age and for piece of mind I plan to replace some smaller dollar items such as the TPS and COIL. Even thinking the ICM might have something to do with this.

From what I gather the VATS system is not the issue because the starter engages and the fuel pump primes, and well, it has started on its own a few times.

Here is a rundown of what the prior owner had done.

New fuel pump, new injectors, new opti spark, new water pump, remanufactured ECM, new plugs, new wires (I found one that the casing has a small rip, though not down to the wiring), and they traced all the grounds.

So yeah, I am knee deep in this car but I believe it's an issue that can be resloved if I am persistent.

Any help/advice is greatly appreciated. I am not too far from Tampa, FL so if anyone ever wants to lend a hand in person, I would not object. I usually pay with food and perhaps an adult beverage or two.

I am accountant by trade so please, be gentle if I am messing something up or not on the correct path.

antfarmer2

It should prime every time from off to on not so much from on to start. I would leave your pressure gauge on and do some testing and see how long it holds. Then post the results. Do not see that you replaced the fpr yet pull the vacumme line of it and smell for fuel.

TLS_Addict

I have not done much yet, just checking for simple things and moving forward. It has primed all but a few times from off to on, and from the run/start position back to on it will prime sometimes. Rarely has it not primed with the key turned fromofftk knand when it has it is after I just tried to start it a few times.

I will pull the vacuum from the regulator and smell for fuel. What is a bad sign, if I smell or do not smell fuel? I will hook up the fuel pressure tester tonight and cross my fingers.

Thanks for your help. Can't thank you guys enough.

antfarmer2

Smelling fuel is bad. Mine primes every time from off to on that I have noticed it might need time to reset but don't know.

TLS_Addict

Thought so, just wanted to make sure.

TLS_Addict

Put the fuel pressure tester on it and and turned the key to the on position and it went to 42 psi and then settled at 40 psi.

After 2 minutes it dropped to 38 psi.
After 5 minutes it dropped to 35 psi.
After 10 minutes it dropped to 32 psi.
When trying to start the car fuel pressure goes to 42 psi and the car fires and the pressure drops to under 35 psi and the car dies.

I pulled the vacuum hose on the fuel pressure regulator and sure enough I smell gas in the vacuum line.

So a fuel pressure regulator is on the agenda for tomorrow night.

Does it sound like I am on the right track?

antfarmer2

check your oil and see how much fuel you have in there time for a change

TLS_Addict

Would a bad regulator keep the engine from running for more than a few seconds?

TLS_Addict

I pulled the dip stick and now can smell just a light bit of fuel.

Tomorrow night I will be changing the oil too.

antfarmer2

Sure sounds like it. The diaphram has a hole in it and sucking the gas in the vaccume system instead of regulating the pressure

TLS_Addict

Well, let's hope that's what it is. Not going to get my hopes up yet. Haha

VeryUnoriginal

1993C4LT1

Im no pro, but I would ohm the injectors for the hell of it. Easy to do. Mine ohmed at 16.4 ish, should be the same for your 92. Guys, he says he only gets code h74. No code c12, doesn't that mean something is wrong with the computer?

TLS_Addict

This has a new/reconditioned computer, but that doesn't mean much sometimes. Haha

I am in luck, my father has a 93 with a spare (new) computer back in PA. I'm sure I can get that from him.

My top is cracked, maybe I can take the other glass top he has. Yes, he has two. He does that stuff. Lll

antfarmer2

You did change your fuel filter?

TLS_Addict

I did. The old one had a little blockage but was fine.

One thing, the H74 shows up in the code 1 when it pops up, in all the other numbers (4 & 9????) There are just three hashes.

Since the H denotes a history cods, wouldn't that keep the C12 from showing? Just typing what I am thinking. I also am thinking of cheese cake.....with cherries, and maybe some chocolate sauce, and perhaps a beer, and Dallas Cowboy cheerleaders.

antfarmer2

You and firstvett are in the same boat I am looking at the icm if the fpr does not work. your fpr is bad if your sniffing gas.

KYC4

Keep at it...I think you are far closer to getting her running than you think. Nice to see this one fall into good hands. I know the gent you bought it from was sick of fussing with it but things do work out for a reason. Please keep us posted.

Happy for you,

Lee

TLS_Addict

Thanks! Trying to fix this beast.

Yup.

I was thinking ICM. I have a coil ready to go on as well if it seems to have a spark issue.

The thing.is, this one fires just fine and starts but dies. Verified fuel pressure and a faulty FPR.

antfarmer2

Put the fpr in and let us know. There is a op having close to the same thing what do you know about the puter doing this too?