I haven't, I will look into it.

 

Here is an old trick I learned to find vacuum leaks. Idle the motor and spray a little WD40 on the suspect vacuum lines. If the idle increases you found a leak.

 

Do a cylinder compression test...it's an 85

 

Finally checked my engine codes, that was so easy I am a lazy bum!

But I got:
15
32
34
43

Looking them up in the haynes manual now.

 

Not going to find ANY answers or FACTS in a $19.95 hyenas manual. Sorry...facts and accurate info required to repair these cars comes in a set of books...that can be found used for $75-$100.

When that arrives you now take the hyenas manual and use it to level a table leg.

Once thats done and the useless info is gone,you can fix the car.

Good Luck

 

15:
Coolant temperature
sensor (CTS) - signal
voltage is high.

32:
Barometric pressure (BARO)
sensor circuit failure.
OR
Exhaust gas recirculation
(EGR) valve diagnostic
switch - closed during
engine start-up or open
when EGR flow requested
by ECM.
OR
EGR/EVRV.

34:
Mass air flow (MAF) sensor
- signal voltage or
frequency is low during
engine cruise.
OR
Manifold absolute pressure
(MAP) sensor - signal
voltage is low during
ignition on.
OR
Pressure sensor circuit -
signal voltage too high or
low (carburetor engines).

43:
Electronic spark timing
(EST) circuit - low voltage
detected.
OR
Electronic spark control
(ESC) - circuit problems.

A factory service manual (FSM) will be your best friend. Keep an eye on the classifieds here and on ebay.

 

Thank you for the info! From the recent posts looks like I'll be getting a FSM.

What do you mean by keep an eye on the classifieds? Like the advertisements are important? lol

What is the easiest way to reset my codes? I want to see which ones come back since I have fixed the vacuum leak (fingers crossed that was the only one), and some of the descriptions sound like my old/clogged plugs, wires, or distributor rotor/cap, which have all been replaced could have been the cause.

 

Like justbob said add it and let it run through the motor. My 93 sat for at least 3 years with old corn gas in it. When i went to pick it up i had a 5 gallon can of hi test with a can of sea foam in it. The car was 75 miles from my house i made it home and continued to run sea foam in tank till it cleared. Everyone has there favorite gas additive that they have used over the years. Put both cans in tank it wont hurt and it might clear it up.It may smoke some and run rough till all that **** runs through the motor.Dave

 

I dont even think it would work to level a table leg?

 

Haha I have one can in now, but I haven't driven it much so I'm still around 3/4 tank but between that and fixing the open vacuum line I found its gotten alot better. You're saying I should go ahead and throw the other bottle in? I was going to do that on the next tank, just seemed to make sense but I'm a newbie with this stuff, my car is older than me.

 

Yeah throw it in and USE it. To reset code pull the negative cable off battery for a minute.Next time try the seafoam,ive been using it for many years in cars and marine engines. And now that we are being forced to burn corn you need it more than ever!

 

Will this reset the ECM also? I read that it can take awile for the system to adjust after fixing a vacuum leak, unless you reset the ECM, but I have driven it 30 miles or so since then and it was running good this morning so that might be irrelevant.

 

So a recap for all of you very kind people helping me.
1985 TPI, Automatic, 154K Miles
Codes: 15,32,34,43
Recent Replacements, Fixes:
Fuel Filter
Spark Plugs/Wires (Done by a friend with limited knowledge)
Distributor Rotor/Cap (Done by a friend with limited knowledge)
Techron STP Fuel System Cleaner running through the system currently.
I did the MAF tap check, never cut off on me.

All the things done so far have, as a whole, dramatically improved the performance of the car.

It runs and drives, has knocks if I accelerate hard.
It seems to continue giving gas slightly after I let of the accelerate for up to a few seconds.
When at a stop light, I have to flip it in neutral and give it a little gas or it will stall out almost every time within 15 seconds.
I had issues with what seemed like irregular acceleration giving constant gas. It would do nothing, then accelerate very quickly, the engine going from a low rpm to high rpm very quickly. This issue comes and goes with varying degrees of severity, but seems to have gotten much better with the recent vacuum line fix and techron STP running through the system.

 

The classifieds here in the C4 section. You could make a post saying that you are looking to buy a 85 manual. Make sure you get one for your specific year.

http://forums.corvetteforum.com/c4-p...ale-wanted-55/

I saw this one on ebay, they're pricey but worth it when you're dealing with a frustrating problem.
http://www.ebay.com/itm/1985-Corvette-Shop-Service-Repair-Manual-Engine-Drivetrain-Electrical-Factory-OE-/230818277262?pt=Motors_Manuals_Literature&hash=item35bdd7678e&vxp=mtr
There are also versions on CD out there for less but I don't find them as useful as as a paper copy.
http://www.ebay.com/itm/1985-Chevrolet-Corvette-Mechanic-Workshop-Service-Repair-Manual-CD-Factory-OEM-/400443171892?pt=Motors_Manuals_Literature&hash=item5d3c45e434&vxp=mtr

 

Oh I see thanks!

Yeah, I see the value in it, at the end of the day I can always sell it for at least 75% of what I buy it for and time is money and from what I hear that will save me alot of it.

 

As part of a tune up I would also replace the o2 sensor. Once you clear the codes, see what comes back. The coolant sensor code and maf codes are big factors on how the car will perform. On the coolant code you can just verify that the cooling system is full as a start. When you get your FSM look into the coolant code, that circuit will tell the ecm when to go into closed loop operation. The coolant sensor for the ecm is different than the one that the dash gauge uses.

 

I wouldn't bother with snake oils or "mechanic in a can" and such. Every few years I take my injectors off on all my machines and have them sent for cleaning and testing. That is, unless you think you can clean a gymnasium in the dark thoroughly since that is what you are trying to do. As to your stated experience, have you tested the injectors before and after? If not, how do you know it works? And your higher mileage engine. Did you disassemble to see what it was like before and then after? If not, how do you know what happened?

 

You just changed the combustion characteristics so who knows. Take the injectors out and send them to Jon at FIC and he will tell you whether it is good or not. For the life of me, I have no idea why people will try everything including a virgin sacrifice before they have their injectors cleaned and tested. If they were Multecs, I'd toss them for the Bosch units. Multecs are going to just love the crapahol the govt insists on putting in the gas after winning votes from the corn farmers. Have you checked fuel pressure with the hose off? What about taping the gauge to the glass and doing a WOT run? Have you taken a propane torch to all you hoses and mating surfaces? If not, that is what I would do. Then make sure your timing is set and then clean the IAC and throttle body then set the IAC using the counts and the TPS.

I'd get a Factory Shop Manual and a scanner that can give you live data that the ECM sees. Makes diagnostics MUCH easier.

 

Check the air filter also.
What plugs and what wires? Make sure that the wires are in right order.
Waste of money, IMO. Send the injectors off for testing or maybe get a new set of Boschs. Multecs are junkHave you bought MAF cleaner and tried to spray clean the wires?

Something is still wrong.
Is the linkage sticking? You need a scanner to see better.
Sounds like your IAC is not right. Again need scanner.

 

Thank you for your input, I have checked the air filter it is new. Discovered a new vacuum leak again, so the good news is maybe I still have the same problem.

I generally agree with you for injector cleaners and such, but its $12 I blow worst case, worth a try IMO and its in the tank now so what's done is done lol