Hi Y'all. Well, I have 2 more weeks of insurance, then 6 months of tinkering and waiting. Decided not to insure the car for the winter.
Still trying to get this thing figured out. Last week I put new gaskets in the TB. Thought maybe it was sucking air behind the MAF. Also installed an airfoil. Although it idles a little smoother, it's not fixed. This week, so far a new knock sensor (didn't help) and a ECM. I found a Blue Streak reman in a S10, less then 2 years old. It's hard to tell whether it did much, cause the car runs fine just daily driving, but still has a flat spot at high rpm.
Seems to have lots of power, but there is a noticable pause in 2nd gear, just before it hits the shift point. It seems fine in 1st gear and doesn't hit high enough rpm in drive (in the 1/4) to notice it.
This showed up at both dyno days as a spike in the curve. Could the stock chip cause that?
Weather permitting I may try it at Cayuga this weekend.
Any last idea's what to look for?
Thank's, Martin.

 

Are you driving my car when I'm not looking? I'm beginning to wonder! hahaha...I also have the flat spot as well. Nathan knows all about it as he had that trouble too before he got his Performance Resource chip. He said once the new chip was in the flat spot went away. So it could be total coincidence, but it could be your stock chip. I'm hoping to pick up a new ECM and chip this spring.

 

Could the ESC module cause the total advance to be to low?

 

Chris, I checked the fuel pressure at higher rpm and it does drop off, which is normal, but I don't think it drops enough to cause the problem. I'll probably change the pump anyway. The pressure should still stay up longer when the car is shut off.
Yeah, I'm thinking (hoping) new chip. Now the question is, aftermarket or custom? I've been told about a guy in Brantford (can get his name) that's suppose to be really good with this stuff. A custom chip is probably the way to go, but I've also heard Superchips is good and Nathan swears by Performance Resource.
This will be fun

 

what kind of ECM?Whats the number on it?What PROM did you use on it?

Daz

 

Hey Daz. The ECM # 1227165 and I took the prom that was in the car..... Delco ABWT 8674. Do you know if that is the stock prom? .... cause one of the first 15 has definitly been into it.

 

martin have you had your car scanned? if not do it. there is a ton of info that you just cant see any other way.

 

Hey Scott. I had the car scanned after I last went to Sparta. The guy told me the timing was out a little, but other then that, everything was perfect. He did recommend checking into an upgraded prom. At this point it seems the thing to do. Unfortunately I won't get to test it out until next year.
Are you looking into it as well?
Martin.

 

Scanned??What did he use??Was it scanned with load?(driving)?That is the proper ECM though

Daz

 

That's just it Daz, I don't know S**t about this computer stuff, but everytime I ask this guy something, he say's he checked and it's fine.
He does have a dyno and runs around like a chicken with his head cut off, but is suppose to be good. As far as checking under load, he say's he did. You would think he should have found something by now, he's had it twice this year. He did say, he could tell it was cammed up and said the PROM is likely the problem.
I also had it at the GM dealer, but it seems, if there are no codes, these guys don't have a clue.
This is the reason I've started throwing parts at it. At least I get something for the money and maybe someday hit the right part
Other an possibly a new distributor, ESC module and PROM over the winter, I'm out of idea's. But it's alot of money to throw away, if it doesn't fix it.
The PROM does seem likely, but I doubt it will have anything to do with why the car runs better with a 7 mil coil wire, then it does with an 8 mil. It doesn't make sense.
Under WOT the 8 mil works fine, but just cruising around and it stumbles with the 8 mil and doesn't with the 7 mil. I'm still guessing there's more then one problem.
All I know is, I've owned over 30 different vehicles and this is the biggest pain in the A$$ I've ever had.

 

Interesting finding thus far. Agreed that I will be replacing the FP in the spring anyway. I'm tired of guessing. I've replaced every possible sensor related to the problem and nothing has work so far. If a new FP doesn't fix it I'll just cross it off as $600 wasted, but at least I'll know at that point. I don't know anything about the ESC but if I can get it for a descent price perhaps I just replace that too.

As far as chip goes...Either custom or PR like Nathan's. I had a ADS Superchip...same company that got bought out by Superchip Inc. and it was a huge waste. That piece of crap cost me about 8HP on the dyno. Thank *** I only payed $30 for it. Just a heads up. A custom burn would be the best if you know of someone that can help you out.

 

I doubt its the PROM assuming its not fried..I was running a bigger motor,injectors and cam than you and running low 13's with it with the stock PROM..Load on the dyno is not the same as load when driving..Did he scan it at WOT?Does he have a log file when he scan it??

Daz

 

Good questions Daz. I don't know if there is a log file. There should be if the work has been done. HMMM.
Well, that's one of the reasons I've never done anything with the PROM so far. Scott is still running a stock one as well and I'm sure other guys are too.

Chris, I'm not sure about the ESC module, but if it's giving the ECM the wrong signal, it could be retarding the timing and not be hitting full advance. Just another guess at this point, but that's old news for me
Another possibility is, if the distributor shaft is a little loose or gear is worn. These are just things I'm going to check into, cause of the coil wire thing, I'm not sure if they apply to your car.

 

if its giving you erratic timing then it should show on a log file..You should be able to see if it advances at certain RPM..Try a timing light at each plug wire and see if the blink is constant(brown wire off)If you see one plug thats not consistent then trace it back all the way to the ECM

What does the plug say anyways?

Daz

 

I've changed the plugs so often this summer, they don't get a chance to tell me alot. I had Busch in at one time and at dyno day, Scott and I thought it was running lean. They seemed to just stay white, even though weeks later the e-test showed it running rich So now I put AC's in, they seem to have good colour. I'll leave these in awhile.
The thing is, I keep messing with the idle screw and fuel pressure trying to get it right. It still seems to idle low for some reason. About 3 weeks ago, I put in a new IAC. Hasn't done a thing.
I'll test the plug wires with a timing light, but I'm not sure what you mean about tracing the wire back to the ECM.
Pretty soon I think I'll just leave it alone and not worry about what it runs. Kinda sucks though, knowing some ricers could blow me away on the street.

 

trace - From the wire to the cap to the rotor to the pick up coil(!) to the module to the ESC to the wiring to the ECM


Daz