alright so my car(1986 iroc z) has been cutting out at about 120 mph due to what seems to be the fuel system being shut off. so i figured i'd try switching computers and see if that would fix it. but when i changed computers (which i did find the correct one i'm not that stupid) the car wouldn't even start. so i took the computer back to the guy i got it from and he advised switching the chips and seeing what happens. so i took the plate off his and it had the stock chip nothing special. when i took the plate off mine i had a A.D.S speed chip for the right model and all. so when i switched them his computer worked fine and it still cut out at 120. so being curious i went and asked a mechanic friend of mine if i could just reprogram the chip to make the car run faster inwhich he replied that the chip was to old of a model to do so and that i needed to get a newer model.

now that all the background info is out of the way lets get to the problem. the problem is that i have plenty of friends that can go faster then 120 in the same exact car and run a stock chip so why is it that my car wont start with the stock chip in the computer anymore?

 

Mind telling us where you're getting up to 120 MPH?

 

820.... there's no one on the highway late at night...

 

I can't say I can in good conscience offer any advice. Doing crap like that on public highways and by-ways is just stupid, no matter how empty you think the road is.

That's not a lecture, that's simply stating the facts.

 

ok people.... so back to the point here.... which is to answer the question of why wont my car start with a stock chip....

 

i agree with five7kid go to the drag strip, as for the 120 cut out i have a 91 transam it cuts off at 122. speed limiter ,i put a switch in that cuts off the speedometer.we have a 2 mile straight stretch right up the road,i only did it twice.when i got the car it had 2:73 gears now it has 4:10s, dont have to worry about it cutting off ,i run it at the strip sometimes.

 

Well, for one, we have no idea from what you've said so far, "stock" what?

 

i'm talking about the chip that comes in the computer when you go and buy a computer from the dealership... this is what i have right now http://memimage.cardomain.net/member...24_37_full.jpg
and its for sure not stock.. the stock one is blue and smaller.(i dont' have a picture of it)
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so what was the speed limiter? was it in the computer or something? or is it somewhere in the wiring harness?

 

What is your car? Year, engine, induction - many different computers with those variables.

 

i have a 1986 iroc z with a 305 tpi motor

 

still needing help here people... anyone else had this problem?

 

okay this again a performance chip is USELESS unless it was actually tuned and tested with the car 2 an 86 iroc doesnt have a speed limiting device 3rd are you sure it is the right ECM as i have heard of TBI computers running TPI systems which could explain this. are you sure you have an I-Roc and not something dressed as one?

 

What does your intake manifold look like B&W?

 

this is my intake.. sorry for the blur took it really quick before i leave.. i'm pretty sure its a tpi motor and i did hook up another (for sure) TPI computer and that's when it didn't run untill i for somereason had to put in my chip instead of using the stock one that comes in a 86 TPI computer.

 

i dont see a pic

 

i don't know how that happened... link didn't even show up... here we go again....http://memimage.cardomain.net/member...24_25_full.jpg

 

okay we are talking TPI here good to know... now where is your MAF? should go between that R-icer air filter and TB...then get rid of that R-icer cleaner and put the stock aircleaners back on will be better+ more surface area...and right there should fix 90% of your problems with the car...

 

i already did that and it still has the problem... its either something dealing with the computer or the fuel regulator... but still the question here is why wont it run with the origional (stock) computer chip in it?

 

were you getting a SES light with the MAF unplugged?

 

yes i was but since i've put the MAF sensor back in the light has gone back off. so i know the computer is good... just wont run with the origional chip. i tried switching back to the origional chip today again but all what happens is the motor turns over and runs till the gas that's "already in the motor" has been burned off. so its like the fuel isn't working or anything with the origional chip but when i plug in my the A.D.S. "superchip" everything works fine. (if you're still not sure why i'm trying to get it to run with the origional chip and why i wouldn't just keep the superchip its because the "superchip" is really old and has a gas regulator programed into it which is why my car stalls at 120 mph i think so if i get the origional chip back in it wont have the stupid regualtor programed into the computer)

 

well i could have told you the stock chip was better... so now what would make you stock chip not function well not run your fuelpump as i assume it primes itself when you turn the key on...sure it is the stock ECM?

 

yes i'm for sure it was the stock ecm cus i barrowed it from a friend who also has a 305 1986 iroc z... i took it from his and used it on mine and it didnt' work... but yes it does prime when the key is on but it doesn't continue to put fuel through the motor when it cranks up
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and it wasn't me that bought the other chip... it was in my car when i bought it and i didn't know this till just a few weeks ago

 

well i think someone has repinned the connectors for your ECU to use a newer ECU you should ask about this in the DIY PROM board they would know more specific information about the different TPI ECUs.. i say that because you swapped a known good ECU in and it didnt work then swapped chips it didnt work... and your stock chip didnt work... but i would think that if you could even plug your stock prom into the ECU that it should work... as newer ECUs would have used newer style chips with different pinsets

 

never thought of that good idea i'll look in to that