Ok guys heres the problem. I have a 40th anniversary Vette non Z-R1. I recently have been having some big problems. My car will run fine for a while (usually 20 mins) till it reaches normal operating temp in traffic (around 180+) then it will start to choke and die, I dont know if it is fuel starvation or to much fuel or anyhting to do with fuel for that matter, also 3 lights come on. The security light blinks and the check engine light comes on and the service ASR comes on as well. Also when it happens my Speedo stops working it stays at 0MPH. I think those are all the symptoms. The car has 19000 miles thats right 19000 miles an I am in Venezuela, Caracas. I cant get any manuals or anything like that. So please any suggestions are welcome. Oh this all started when I ran out of gas, I filled her up then all of a sudden it starts giving me problems, the exhaust also pops or backfires as well and lastly after about 30mins in traffic driving WITH the problem the check engine light goes away and then it can idle smoothly without dying SOMETIMES THAT IS, this is all done with NO A/C by the way. When I do turn the A/C on it gets worse (Stalls more often). PLEASE HELP ME IT HAS BEEN GOING ON FOR THE PAST WEEK AND IS DRIVING ME MAD:mad . I already tried fuel injector cleaner doesnt help and I removed and cleaned throttle body didnt help either.

Thanks in advance, any questions just ask! I dont think I forgot anything and if I remember anything I will edit this. Thanks again! :chevy

 

Two things:

Change the fuel filter - 19000 miles mans the car sits alot....running the tank down could have pulled crap into the filter.

Check the grounds...there's a bunch of ground wires that go to a bolt on the bellhousing of the transmission, it _might_ explain the lights you're seeing.

Any way to get a hold of a Diacom or AutoXray and see what the computer thinks is going on?


[Modified by RocketSled, 8:03 PM 7/3/2002]

 

No computers here in this 3rd world country! I will get the fuel filter changed and get the tank cleaned as well. Where is the fuel filter by the way. Oh and where are the grounds you speek of. Thanks a million man!

 

A large number of grounds are located on a bolt that attaches the bellhousing to the block on the driver's side. You'll need a wobble extension to reach them. (Or a universal joint with electrical tape wrapped around it so it doesn't flop everywhere)

You'll want to pull the nut, remove the grounds, clean everything up and reattach firmly. It frequently solves odd multiple electrical problems.

While you're at it, pull the battery cables and wirebrush them, make sure they're clean and reattach. It doen't have anything to do with the symptoms youre seeing...it's just good hygene.

 

You need a service manual and a scan tool. The scan tool will allow you to find out what error code is stored and the manual will tell you what to start checking. What is the voltmeter reading when your engine starts to fail? It sounds like you could have poor battery cable connections and falling battery volts. It certainly won't hurt to remove the battery cables, ground first , clean them and the battery posts and replace, ground last.

 

I am betting on a bad fuel pump. The FP is lubricated with the fuel itself. When it runs dry it will fry quickly. The lights you see are most likely due to the engine speed falling and the alternator slowing as a result causing low voltage and thus the ABS/ASR light to come on. A fuel filter swap is in need as well the fuel pump and attatched filter on the pick up. It should cost about 75 total and take you less than 2 hours to complete. It is all done via the cas cap.
Best of luck,
Robert

 

Your fuel filter is on the passenger side. it is right behind the front wheel. it runs along the frame. do a search. there are many tricks to changing it, don't attempt it without doing some reading here. but with a little background on it, you'll do the filter in under 30 minutes...

I ran out of gas in my 92 ONCE! as luck would have it my gauge stopped working, but I also ran out at a stopight, accross the street from a gas station! I haven't had any problems since. but I've also changed my filter 3 times over a 40,000 mile span... good luck.

ohhhh yea, you can check your codes through your climate control display, with out a scan tool.... just look up the proceedure with another search. or if you find nothing... email me, and I'll explain how to do it.

and if you plan on doing the grounds, I'd try the filter first. those could be difficult with the exhaust on....

 

Does it still have a catayltic converter on it? Does it seem constipated if you try to spike the gas? I'm just wondering if you got some leaded gas or bad gas that clogged the cat??

Definitely read the codes from your instrument panel. Take advantage of the offer of how to read them. I have a '90 so I don't know if yours would work the same as mine, or I would offer.

 

First thing, Never beg, come on, your a Corvette owner, we never beg...... :lol: :lol: :lol: :lol:

That's what we're here for, to help fellow vette people.
Most of these posts are dead-on. You may have fryed the pump, the fact that it runs good for 20 minutes tells me your pump is ok, or maybe border line. Checking the grounds is a good idea. Don't be suprised if it turns out to be your ECM. What's happening is your computer is reverting to "Limp Home Mode". Inside the ECM are many gnd points. To make a long story short, same thing happened to me, spent more than 75 hours trouble shooting, to no avail . . . . . . A friend suggested the ECM, I took it out & down to the dealer (GM rebuids them, so you need the serial number & the core) put the rebuilt one in, end of story.. Just trying to help.......

 

Ok guys, heres the verdict. I changed all the spark plugs, changed fuel filter, and got Injectors proffesionaly cleaned. STILL NOTHING! I got a mild improvement, no longer dies! But still same rough idle and will not go above 3000RPM's! What else is there. People here tell me to change the IAC valve, other say that I should change the 02 sensors in the cats. Please anything else! :confused:

 

Have you checked your fuel pressure? If it's good across the board then:

What's the condition of your ignition system?

For all the moving parts in your motor, it only needs air, fuel. and spark to run (abeit at the right times and in the right quantities) If you're positive it's not fuel related, then you've gotta look at spark next.

Now is the tim to buy that $100 helm manual. Roll it in as an expense of THIS repair, so that you have them for the rest of the time you own the car. Sadly, if you'd HAD them, you probably would have found a few very direct tests that would have positively determined what's going on. Now, all you can do it throw parts and money at it and hope. That's not a very efficient way to repair cars. :(

 

I have a scan Tool plus the Fault Code Diagnostic Ground Plugs fro Gordon Killebrew. His Phone # is (615)654-2864 USA. You can get them from Mid-America Designs (800)500-8388 for 1982-93 part #604-259 1993-96 part #604-260 either one for $39.99. It uses the DIC and service engine soon lights to display trouble codes. If this helps.

 

You really need to pull the codes to find out what the ECM is trying to tell you. You are throwing parts at the car in hopes it fixes the problems. Take the advise of the other posts above this one and spend some of your $ on a code reader. It will point you in the right direction and in the long run will save you some money by buying just the parts you need to fix the problem. :yesnod:

 

As someone else mentioned- Check the catalytic- these things go bad overnight! Sounds exactly like typical symptoms.

 

When the temp reaches op'g speed, a circuit board in the ECM is expanding, killing/shorting a circuit that carries ground. That's why "0 Mph" on speed readout, various system lights coming on the D.I.C. (digital instrument cluster), and the "Limp Home Mode" takes over ! ! ! A new one will cost about $150.00.... ok, I'm done here.

 

I agree with the suggestions for a bad ECM. The speedometer reading going to zero is tip off that the ECM could be bad. It doesn't fit with the rest of the problems. Your opti distributor maybe bad as well. Not reving above 3000 is a common failed opti symptom.

Have the fuel pressure checked to see if the fuel pump is bad before you go looking for ignition problems. Do this at 3000 rpm too since thats where the power is falling off. Make sure your getting at least 12 volts when the car is running.

One other thought. Make sure the connection for the speedometer sensor is okay. If its bad or intermittent, the ECM might think your not moving. When the computer thinks the car is not moving, it just lets the idle fall to what it was set to. When it thinks the car has decelerated it will drop the idle slowly to prevent a stall. I know this because I had a programming problem with my setup and the ECM was showing 0 mph and saw the same idling symptoms.

 

Sounds like it could be ECM....I just replaced mine last year....ck out this thread to pull codes without a reader......http://forums.corvetteforum.com/zerothread?id=337870


[Modified by vette5, 7:08 PM 7/8/2002]

 

clogged exhaust/cat? :confused:

 

Ok guys heres another update, I just got my car put on diagnostic computer Called the (OTC Monitor 4000 Enhanced) It pulled 2 codes, 66 and 32. What are they?? I read vaguely that Code 66 was a Pressure sensor ground for AC or something like that, and that code 32 is EGR system 02 sensor or something like that. Please enlighten me on these codes so that I can fix this problem once and for all. Thanks! :chevy

 

I understand your confusion, when mine (ECM) went, it gave me several strange codes, my right front wheel speed sensor was bad, the ABS sys was bad, a few others . . . . . . . Hence the 75 hrs of trouble shooting, doing continuity checks, voltage checks, ohm checks, etc, etc, etc. . . . Think about it, if it's grounding circuits that shouldn't be grounded, it's gonna relay things that don't make any sense, right ? Right ! ! Take it to a dealer and have them check the ECM, can't do it out of the car. . . . Or, drop $150.00, about, and replace it..
:cool:

P.S. Don't forget to pull the chip out before you exchange it, your dealer should tell about this, but just incase they don't ! ! ! ! ! ! ! ! ! ! ! :nono:


[Modified by edsalinas, 1:11 AM 7/9/2002]