rolando4812

for the whole time i have had my car this has been a problem. when the reading shows that the coolant is around 130-155 and the oil temp still says low the car pulls and pushes me in the seat. but at around 160 and up it seems like it looses some power. any help?

CFI-EFI

At lower temps it is in open loop, running off of preprogrammed values. Once it is up to temperature, it goes into closed loop and runs poorly. I'd say the first step is to check to see if there are any codes set, and then correct them. I'm guessing you will find trouble codes.

RACE ON!!!

rolando4812

how do i check for codes? thanks

vinnies87

FYI: easier if you put your yr in the post... but other than that, use the search function - theres been tons of archive post with the proceedure. paperclip process or get a reader from Autozone

86PACER

Is your engine light coming on while driving?

http://corvettebuyers.com/c4vettes/ecm.htm

GS4-LT1

Going from 170 to 200 degrees is worth about 2 tenths slower at the track for me. I think its just the nature of the beast to loose a little power the hotter it gets...to a point.

rolando4812

thanks guys sorry its an 85 its in my profile
and yes my engine light is on all the time

AGENT 86

Use 86PACER's link and find your stored codes.

CFI-EFI

The constant "Check Engine" light should have been your first clue. Some very important advice from that link:

"The central point to keep in mind when troubleshooting the codes is there is no reason to automatically believe a sensor has failed. It is possible that a sensor itself is exhibiting a hard or a intermittent failure but it is more likely that a connector has gotten dirty, a wire has broken or some underlying problem is present and the sensor has done it's job.

For instance, a Mass Air Flow (MAF) error code is often a dirty connector at the MAF sensor as opposed to a bad sensor. Similarly, a code indicating a lean condition can be timing, fuel delivery or dirty/plugged injectors. The codes are normally a symptom, not the disease.

Do not immediately buy a new sensor in hopes that will fix the problem. Look into the problem a bit more first using the links from the code table as your guide and consider buying a scan tool so you can determine exactly what your ECM/PCM is being told by the various sensors and---just as important---how it is reacting to the sensor inputs."

The FSM has trouble shooting charts for each of the trouble codes, plus other driveability problems. If you will follow the charts and test any components you suspect are bad, before replacing them, you can save a lot of money by NOT throwing parts and money at the problem.

RACE ON!!!

86PACER

Yes, pull the code(s) then report back with the code numbers.

Sam Lam

The paper clip used to short terminals A to B will work. However, you can go to Auto Zone and get a GM Diagnostic Key ........ for FREE. This is a convenient substitute for the bent paper clip and a mell of a lot easier to use.

86PACER

None of the Autozones here had that key. In fact, they had no clue what I was even talking about. It's also not even on their site. Apperently it depends on where you live.

pcolt94

Last time I got a code key from A/Z was in the mid 90s for a Firebird. They may not carry them any more.

rolando4812

thanks guys. i'll stop at autozone tonight after work and see if i can get one if not i'll use a paperclip. i'll let you all know of the codes i get

rolando4812

alright there was only two.
1. flash pause flash flash
2. flash flash flash pause flash flash flash.

thanks for the link. very useful but i can't make out what codes these are. a little help please. thanks

Road Agent

This advise is dead on!

86PACER

You have a code 33. MAF code. Ask Agent for the pdf file.

Count the flashes.

It goes like this. The first series of flashes is the first digit of the code. Then a short pause. Then the other flashes is the second digit of the code. Then put the two together. That's one code. A long pause seperates the codes from each other. Each code flashes 3 consecutive times before moving onto the next.

Code 12 is not a trouble code. It indicated the beginning and end of the test. Any codes in between the two 12's are the trouble codes. If there are no trouble codes, all you will see is code 12. When you see code 12 again, it means all codes if any have already been displayed.
1 [short pause] 2 = Code 12

long pause then,

3 [short pause] 3 = Code 33

CFI-EFI

Each code flashes three times. Number one is code twelve. It should have flashed three times before you saw number 2. Then #2 should have flashed three times. After the three #2s, there may be another code. If so, it will come after the #2, and flash three times like the codes before. When it starts flashing twelve (#1) again, you will know you've seen all the codes. Code twelve is not a trouble code. It is an all OK, signal saying that the ALDL is communicating with the ECM and sending the codes.

Number 2 is code 33. On my car that is a code for the MAP sensor. Your '85 doesn't have a MAP so I am guessing it is for your MAF. Pay heed to the excerpts I copied from the link and pasted above. Now follow the trouble shooting chart in your FSM for a code 33 and fix the problem. If there were more codes after the #2 (33) correct them in the same way AFTER you have finished with the code 33.

RACE ON!!!

AGENT 86

http://members.shaw.ca/corvette86/Code%2033.pdf

rolando4812

thanks everyone for the help. now i'm following the steps that are on agent 86's link. sorry bout the question i have never done this before. in the 3rd box it says "jumper alcl terminal 'g' to 12 volts using a fused jumper wire". how do i do this and can i get a jumper wire at auto zone or pep boys? thanks guys