My Vette is very sick, Please read and help if you can

[Red89]

Hi guys I put a chip in that I got from Jeff, The car ran ok but it had an oil leak so into the shop it went. The shop found that the seal for the Dist. was leaking so with that fixed it was also time for a tune up.

After new plugs, plug wires, Dist. Cap roter button, PVC Valve, and Fuel filter the car ran like $_ _ T. So another dist cap was put on to make sure the first one wasn't bad. and 2 more sets of plug wires to check and make sure that all the parts were ok. and with no codes coming up on the computer the car runs VERY rough.

What are we missing???

Any help would be appreciated.

the next thing I'll do is put the old chip back in to make sure that's not causing my car to be so sick.

Thanks for any help

Byron

 

[*89x2*]

the next thing I'll do is put the old chip back in to make sure that's not causing my car to be so sick.

That's where I would start remember to wear an ESD strap while playing w/ the ECM

 

[bill mcdonald]

seal for the dist????
This tells me they removed the distributer from the intake, right?

Well if swapping the chip is easy enough, try it. but if it worked fine before, I would think it should be fine now. But this sounds easy enought to do before I go on here.

What exactly is sick? Missing, not ideling?

I would look at all wires involved in removing the dist, and inside the dist. Since they put 2 different caps on it, I asume they moved the coil both times, and I think odds would be, if they messed something up in the coil wires, it would be fixed the second time they installed it. So I would look inside the dist for my problem.

Maybe a wire was pinched under the cap??? things like this I would look for.


Are the wires in the correct order (double check)?

What is your timming set at? Was it set with the black and tan wire disconnected? if not you would have a the wrong timming set and I bet this would make the car hardly run.

Who worked on the car?
Have they done this to a vette before?

I mean a few things can be screwed up, and I dont know where to start. Lots of things were done at once so that leaves a few things to go over. Plus I dont really know what is wrong with the car.

 

[Red89]

My sick car

what I mean in "Sick" is that it will hardly idle at all and runs very rough at all constant speeds, The funny thing is when you floor the gas it runs great burns rubber for 40 feet and even chips 2nd. very hard. the thing runs like a race car when you get into it. but its sick on the highway and at idle.
Thanks for any help...not sure if my mechanic had the black/tan wires hooked up when or if he set the timing...I'll be talking to him soon.

Thanks again...this is why this forum is great
Byron

 

[cntrhub]

Well Byron, I don't think it's a wire problem. If you say the tires squirt in gear, it seems there's not a fuel problem, or a wire problem that would short to ground? So bottom line is.......change the chip back to stock so you get a baseline. If the car still runs like "excrement".... I think you might have the distributor off a tooth or two? When you look at the distributor, does the cap look like it's pretty much in center or does it look twisted over to on side, stretching the plug wires? You have the sequence of wires to plugs correct.....right? I'd make sure you have each wire off the distributor going to the right plug. Just to make sure. A broken spark plug will drive you nuts if you don't have accesss to a strobe machine to check the ignition system firing on the TV pattern screen. "If he set the timing...."???? I'd talk to him big time!

 

[bill mcdonald]

Any updates?

 

[Red89]

Well Men I've put the old chip back in and still the same problem.

The car runs great "idle that is" until it warms up about 4-5 mins. the car also runs great as long as your adding more power to whatever speed your doing...again if you floor it, it smokes the tires... even with the old chip back in and it still chips 2nd.

I've been told that

 

[Vettelt193]

is the check engine light on? The reason (I think) that it runs fine until it warms up is the computer runs a set way until it warms up, so you should notice the problem start around 160 degrees. At this time the computer takes all the sesor information and adjusts the engine to run best. If you have a bad sensor, it will really mess things up. The first places to look normally are the TPS and the MAF, but that doesn't seem to fit the work that was done, unless your mechanic took the MAF out and accidentally broke it?

 

[vigman]

Check the following

In the NEW cap... the kit comes with a new center button that mechanically touches the rotor in the distrib..

1) I have seen that assy put in reversed so you have an air gap which causes the spark to misfire.

2) The Coil itself.. the wires get brittle and snap internal of the insulation.. or are hanging on by a thread.

3) Rust on the coil frame.. so you have a poor
ground.


And discuss the timing procedure he used..IN DETAIL.

Sounds like spark to me...

Vig~

 

[-=Jeff=-]

So Both PROMs work the samre right? cause the problem? If it does turn out to be my PROM , PLEASE send it back to me to see what could be wrong and I will re-burn a new one for you to try..

Although it sounds like the Distributor is off a tooth or two.. again as everyone else has said..
Keep us posted

 

[matchframe]

Have you checked for vacuum leaks?

 

[Red89]

Thanks for the tips guys...back to the shop today...I'll let you all know what happens

Thanks again

Byron

 

[Red89]

Well I still have a miss when the car warms up.

My mechanic can't get a connection with the computer to read any codes. And I don't have a check engine light or service engine light. again all parts are new...Plugs, wires, Dist. cap, Button, PVC, no vacuum leaks, timing is right, old chip or the new chip I got from Jeff...By the way Jeff’s chip makes the tires spin and the old chip just gets me up the road fast so if you want to buy new tires often then buy a chip from Jeff.

I just wish I could fix this miss. I don't want to just start buying parts and seeing if I needed that part or the next one... how much is a MAF or a TPS?

The one thing you guys said is that maybe the Dist. is off a tooth or two...but could you get the timing set if that was the case? My mechanic says it can't be off but I didn't see him check to see if it was off a tooth or two???

Thanks again still

 

[bill mcdonald]

Again I am going to ask, what background does your mechanic have with working on this year vette? Is this a buddy or something?

The TPS can be checked with a volt meter for proper function. He should know this. you hook it up (I forget what 2 wires) and you can move the throttle body open watching the voltage. you should see .54 volts with the throttle closed, and it should work it's way up to 4 volts when wide open.

Pulling codes from the car is elementry.
all you need is a paper clip bent into a U shape.

Under the dash, where your right knee would be is a terminal to plug into. If you shove the U shaped paper clip into the A and B terminals, and put the key into the ON position, the check engine light will flash codes at you. You might also hear the fan turn on in the engine compartment.

The A and B terminals are the very top right 2 ports on that terminal. I use mine so much I wired in a switch to turn it on and off.

Now to get a code, the check engine light will flash for the number. a flash pause flash flash, will be code 12. on my car this is the first code to flash.

A flash flash pause flash will = 21. get it?

each code will flash 3 times in a row, then move to the next code.
so you should see something like this
flash pause flash flash
long pause
flash pause flash flash
long pause
flash pause flash flash
long pause
then the trouble codes will come after this set.

you can post the codes you get here and someone will tell you what they mean if you have a problem.

If you engine light is not on, but works, then you should not have any codes.

I am also wondering what the mechanic set your timming at?
Do you know how to use a timming light?

What did he mean by it cant be off? yes it can.

Did you tell him about the black and tan wire that needs to be unplugged when you set the timming????

This wire is stopping the computer from moving the timming around at idle so you can adjust it. if it was plugged in, and the timming was set like this, the timming is screwed then.

And I have set the dist off a few teeth, I had to make up for it with turning the dist a lot. this was not on my vette or a computer controlled car though. there is no room for me to error on the vette, or the cap does not fit unless I am right on(I have a super ram).

Sorry I dont know anything about MAFS. but you might want to look for air leaks after the sensor.

from your desription, it sounds like the car does not like being in closed loop, which is when it is warmed up.
I went through this with an exhuast leak on a set of headers. it idled great, but chugged when I went to accelerate, and pulled right out of it at wide open throttle like nothing was wrong. this was from the O2 sensor getting false readings from the exhuast leak. Just another thing to think about.

 

[BigRed]

Typical Chev....

Ok have your mechanic entertain the idea that he cracked the magnets in the distributer. Our shop does like a dozen of these a month (mostly from the trucks but anyways) Chev's are VERY weak in this area. The magnet (If cracked) will most likey be in four pieces still being held together by the shroud...so look hard.

Spark is being shot at random and its my guess thats what your problem is. The first time I got this problem in I spent a day screwing with caps, rotors, ECM issues, etc... But as you say the guy yanked the Distributer which is a good lead to the problem.

Its VERY common to have a symptom like this for this particular problem.

Also make sure the distributer isn't 180 degrees out and the vaccum lines are ok.

Find out if the mechanic or you can dig up a working HEI Distributer and dump it in making sure that number 1 cylinder is where its supposed to be and it facing the right way.

 

[Red89]

Hi Bill Mcdonald

I don't know you and you don't know me but I'm touched by how much your trying to help me...you now have a friend in MD if your ever this way I'll put you up for the weekend just for you being so nice to me about this problem.

The shop is owned by a friend and he is not a vette guy but I can trust him to be honest and fair with me...were all looking for the fix and he's not charging me a dine if he can't fix it.

I do know he pulled the tan/black wire when he set the timming... the Dist. does look off center but he again says the timing is set right.

I'll print your responce out and back to the shop I go.

Again thanks for your help.

This is the best forum I've ever seen or heard of.

Byron

 

[Red89]

I hooked up the paper clip and got a code #12 what does this mean???

Thanks

Byron

 

[Vettelt193]

12 is a good thing, all it means is the system is telling you the codes. code 12 should always show up, if there are no more, then you don't have any codes set.

 

[Bob Yates]

Did your mechanic put the ground strap which is under the coil back in . I have seen the best and even myself miss this one.Also to check if the distributor is in time. Remove the left valve cover. Turn the engine over until the number one cylinder's intake valve opens . Go to your timing mark on the balancer and bring it up to the mark that is top dead center. Check where the rotor is pointing it should be at # 1 wire on the cap. I understand if this sounds complex. It took me years as a mechanic to get this down and still sometimes I mess up. Good luck.....Bob Yates

 

[bill mcdonald]

Red 89, Dont mention it. I have been through 2 months of pain after I completly rebuilt my 90 engine. After spending lots of money for speed, it was a slow pig. I was very angry with it until I got it worked out, I dont even know what the problem was.

Code 12 will come up first every time. this tells you things are working. Did you guys watch for code 12 to flash about 4 times in a row? (it will blink code 12 three times in a row, then move to the next code number. if nothing is wrong, it will blink code 12 forever)

I guess we could look at the simple things. what kind of plugs were put in?
were they platnums? (I have had bad luck with these)

what gap did the plugs get set at?
Has your mechanic pulled any plugs? (I know it is a pain in the ass)