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Discussion Starter · #1 ·
I was driving my car down the road with no problems. Then out of the blue the cel light pops on and my ecu go's into limp mode. wont rev past 4000Rpm and has no power and the idel went up to 2000rpm. It was still driving and starts up fine so i tulk it home to check the cel. One problem there as soon as i jump the conecter nothing happend the light just stays on no blinking at all. So i decide to clear the cel and see what happens. Cel didnt clear and i still cant jump it. Normaly when i turn my key to the on positon the light comes on and then goes away now when i turn my key to the on postion the light stays on. So since i cant find out what code im runing i decided to start the car and get under the hood and unplug senors if the car dies that meens that senor is good right? So i unpluged the map car dies. I start it back up and go to tps unplug that. Car stays the same dosnt die out. You think it might be my tps? Or dus the computer not use the tps in limp mode?
 

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Discussion Starter · #2 · (Edited)
Ok so i just went out there to mess with it some more. I hurd the main relay under the dash making a clicking noise so i unpluged it and pluged it back in cel go's away car starts up fine and runs good for just a few seconds. Relay starts clicking car dies i start it back up and it has the cel again. I also here some thing clicking under the hood
 

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try this:
clear the codes, start the car. with the car running, unplug any sensor that should throw an immediate code like the iacv or coolant temp sensor or map sensor or something. then shut the car off, turn the ignition back on, and check for codes now. see if it registers any codes for the sensor you unplugged.
let me know what happens
 

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Discussion Starter · #4 ·
try this:
clear the codes, start the car. with the car running, unplug any sensor that should throw an immediate code like the iacv or coolant temp sensor or map sensor or something. then shut the car off, turn the ignition back on, and check for codes now. see if it registers any codes for the sensor you unplugged.
let me know what happens



Ok so i did what you said and i still cant get it to read a code. What i hurd clicking under the hood is the evap purge control solinoid valve. Now if i turn the key off and on with out starting the car a few times. then it will let me read the ecu. But i dont get enofe time out of it befor the relay and the purge starts clicking then i cant read the code the engine light just stays on. It realy weird i dont think i have ever seen a car do this.
 

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check the ecu fuse and the clock fuse, make sure neither of them are blown

check all your grounds.

if those appear fine, im sorry to say, you may be the first customer of mine ever to actually have a damaged ecu, and i think i know exactly whats wrong with it too.

take the top and bottom covers off your ecu and take pics of the left side (plug side) of the board, top and bottom, and send the pics my way.
im thinking the iacv transistor in the ecu may have fried, which screws several things up, and is usually caused by people mixing up the iacv and purge solenoid plugs.
 

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Discussion Starter · #6 ·
Thats what i was woried about is the ecu being bad im taking the pics right now and ill send them to you. I know i dont have any thing hook up wrong on my car it is almost imposible to plug the purg control and iavc in backwords and this is the fist time i have thrown a cel since i got the ecu back from you.
 

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i dont remember, did you supply the ecu or did i?

and the better quality the pics can be, the better. some of the stuff i'd be looking for in the pics is pretty tiny lol
 

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Discussion Starter · #8 ·
i dont remember, did you supply the ecu or did i?

and the better quality the pics can be, the better. some of the stuff i'd be looking for in the pics is pretty tiny lol
I sent you my p28 ecu and it got lost or sent to the wrong person so you had to send me a p06 ecu. if you need better pics than what i gave you then ill try to just let me know what you need.
 

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I sent you my p28 ecu and it got lost or sent to the wrong person so you had to send me a p06 ecu. if you need better pics than what i gave you then ill try to just let me know what you need.
ah yes, i remember very very well now. i made absolutely sure that ecu was 100% perfect mint condition. so now im thinking its not ecu, cuz i know what that ecu was and where it came from.
after seeing the pics you just pm'ed me, i can't see anything wrong either.

when you took the covers off, did there seem to be a decently strong burnt plastic smell at all?
on the bottom of the board, can you see any blackness or what could be some form of burn marks?
 

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possibly a main relay issue then

the main relay powers the fuel pump, injectors, purge solenoid, iacv, and egr valve iirc. it also has a trigger wire to the ecu to activate the cel during fuel pump priming when you first turn the ignition on, and a starter trigger wire.

see if you can get your hands on a different main relay and test it out see if it does the same thing or if the problem goes away
 

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Discussion Starter · #12 ·
Ok cool ill try that out and let you know i was thinking mabey it was the main realy to if it wasnt the ecu. Ill let you know what happens
 

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Discussion Starter · #13 · (Edited)
well today i had my freind come buy with his ecu (you also did his ecu). I ran his ecu in my car with no problems no cells ran great. Put my ecu in my car and same problem cell light comes on and car runs in limp mode. My ecu looks fine so i decide to swap his chip over into my ecu. when I ran his chip in my ecu car ran great no cell no limp mode. so i put my chip in his ecu and ran it. When i did that it went into limp mode and threw a cell. So dose that meen that the chip in my ecu went bad. Also dose that meen since its runing in limp mode its runing limp mode for the p06 motor since thats its original program
 

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well today i had my freind come buy with his ecu (you also did his ecu). I ran his ecu in my car with no problems no cells ran great. Put my ecu in my car and same problem cell light comes on and car runs in limp mode. My ecu looks fine so i decide to swap his chip over into my ecu. when I ran his chip in my ecu car ran great no cell no limp mode. so i put my chip in his ecu and ran it. When i did that it went into limp mode and threw a cell. So dose that meen that the chip in my ecu went bad. Also dose that meen since its runing in limp mode its runing limp mode for the p06 motor since thats its original program
yup, that would definitely imply that the chip went bad. good idea in trying that out, never even crossed my mind to check that as chips going bad like that are extremely rare unless it was ever installed backwards by accident at any point in time.
as for the limp mode thing, honestly noone really knows what it does, whether it reads from a totally seperate part of the ecu, or if it automatically modifies the main chip in any certain way, no clue.

i'll get a new chip sent out to you asap no charge.
but before i do, how did it run before it went bad?
i save all basemaps i make, so i can send you the exact same map you had, or i can send you one identical to your buddy's. let me know
 

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Discussion Starter · #15 ·
The car ran great befor it pulled hard and ran realy good. The only problem i had out of it is running on the rich side. When i start it up in the morning it will smoke black untill it burns all the carbon out. Freinds tell me when i get on it and shift it would smoke a little black to.
 

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The car ran great befor it pulled hard and ran realy good. The only problem i had out of it is running on the rich side. When i start it up in the morning it will smoke black untill it burns all the carbon out. Freinds tell me when i get on it and shift it would smoke a little black to.
k, i'll whip something new up for you. i'll let you know when i ship it.

same address, 125 budd st, correct?
 

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Discussion Starter · #17 ·
k, i'll whip something new up for you. i'll let you know when i ship it.

same address, 125 budd st, correct?

yep still same add. Thanx for helping me out and giving me a new one not to many people would do that. most people would make me buy a new one. Just give me a good reliable street tune and thanx again
 
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