SOHC problem (Manual)

[Custommx3]

Ok guys this ones got me boggled.

Local guy here named Jeremy (wastedfaith on the UBB) is having a serious problem. HIs car starts, when cold, but once the car reaches operating temp, it dies. If he keeps the RPMs above ~ 4500, it will stay breafly running, then dies. His Charge light does come on, but he recently changed his alternator, thinking it was the problem. He got the alternator form a local salvage yard, and they "Supposedly" tested it and it was putting out 70 amps. We have un-pluged the Air bypass vavle, but still shuts off. I have put it in Diag mode w/ the grnd/Ten, but still shuts off. Plugs/wires/Alternator (even though used), Coolant temp sensor, as well as thermostat,battery, and fuel filter have been replaced. we cant seem to find any vaccume leaks, and the ECU is reporting a coolant temp sensor problem, even after replacement. Im thinking its the alernator due to the charge light, but I cant be sure. The car has high mileage. I thought it was distributor, seeing as if I had a similar problem and so did my neighbor in his mx-6, but they were V6's, and we didnt have a charge light. We have no other SOHC's around here to sweap parts, and being on a budget, parts are expensive. Anyone have any suggestions other than what I have already tried?

Any help would be greatly appreciated. We have a meet Sunday, and he really wants to go.

<small>[ June 11, 2004, 03:47 PM: Message edited by: Custommx3 ]</small>

[atlantamx3]

Rip that piece of crap SOHC outta there & swap in a BP.

I think someone on the clubprotege forums was selling a BP/Tranny combo for like $250 or something.

Being cost prohibitive, however, If he wants to bring it to the meet, tow it.

SOHC's SUCK!

LOL

Sorry-- No good advise here, only sarcasm.

<small>[ June 11, 2004, 03:53 PM: Message edited by: atlantamx3 ]</small>

[papa roached]

there are two coolant temp sensors on the SOHC, there is one for the gauge and one for the ECU, the one for the gauges is easy to get and only has one wire on it, the one for the ECU is down between hte runners of the intake close to the front of the motor under the fuel rail, it has a green plug i think and two wires coming from it, i had nothing but probs from my SOHC because of that sensor and we kept thinking it was the one for the gauge

<small>[ June 11, 2004, 04:05 PM: Message edited by: papa roached ]</small>

[wastedfaith]

ok...i have the latest update with my ****ty SOHC...i drove for about 10 miles, and stalled turning into a parking lot to avoid a red light because i have to 2-foot it to keep it running...anyway, my grandfather-in-law came to try to pushstart my POS, because ive had better luck push starting it than crankstarting it...anyway, when he attempted to pushstart me, my engine would rev, and sound like it was attempting to turn over, but my RPM's didnt move at all....i asked a mechanic about the problem, and he said from what i told him it sounded like it was the MAP sensor...if possible could somebody give me some info regarding the MAP sensor? location...cost...difficulty...possibility of the MAP sensor being my problem.


thanks,

jeremy

[papa roached]

the SOHC MX-3 does not use a MAP sensor, sounds like your car will run for a bit then randomly stall out like mine dide, replace that sensor i told ya about, why would hte ECU report it as a code if it wasnt bad?

[wastedfaith]

ok...i have found the temp gauge for the ecu paparoached...green plug, two wires...its all there...when i ran my codes, it gave me a code 9, which is engine coolant temp. i replaces the temp sensor for the gauge, but i still get the #9...i guess this is what i need to replace...only problem, whats it called at autozone? when i had them check for a temp sensor, the only one that showed up was the one for my gauge...??????

[papa roached]

take it out and take it in, tell them thats what you need, i had to take mine out and take it to NAPA, i dont remember the technical name for it, i kept changing the temp sensor for the gauge on mine till i figured out it was that one

[wastedfaith]

do you remember how much you paid for it????

[papa roached]

was like $10-$12, been a while man

[wastedfaith]

thanks for the help paparoached....ive been buggin the **** outta barry tryin to get help figuring out what the prob. is, and i feel kinda bad about buggin him so much....hopefully this will help, cuz its getting rather aggrivating...

[papa roached]

mine would run for a while, then die, try and crank start it and it would just crank and crank then act like its gonna go and die, let it sit for a while and it would start up and be fine for a while, turns out the sensor's nonconductive coating on the inside wore off and it was shorting out on the sensor case on the inside forcing the motor to go full rich and die, and it would start till it say and cooler or something bumped the motor to make it not conduct no more, kinda like your push starting works better because it bumps the motor around

<small>[ June 11, 2004, 06:57 PM: Message edited by: papa roached ]</small>

[wastedfaith]

sounds exactly like what mines doing...thanks man...im on my way to get it now...ill update ya...ill post around 9 again

[papa roached]

alright man, let me know if it fixed it, mine also had a random blinking CEL too

<small>[ June 11, 2004, 07:04 PM: Message edited by: papa roached ]</small>

[papa roached]

UPDATE! :p

[wastedfaith]

ok...heres for the long awaited update...i got the sensor, put it in, and now i start fine, run fine, and when im at norm. running temp and shut my car off, it starts right back up...now for the newest problem (which isnt anywhere near as aggrevating as the previous)...if i turn my a/c on while idling, my rpms slowly drop until shutoff and i have a slightly erratic idle...im thinking i need to remove and clean the aic valve and/or possibly throw a new(used) maf sensor in the mother flunker...i need more 411 about the aic valve and its location in relation to the throttle body...(sorry im on used car # 3 and mazda #1, so im still a bit of a newb)...any help would, of course, be GREATLY appreciated...and once again paparoached, thanks alot for bringing that other temp sensor to my attn....i owe ya one...

jeremy

p.s. - i forgot to mention, my check engine light is no longer coming on, but i am slightly overheating (almost to the line before the H)

<small>[ June 12, 2004, 07:04 PM: Message edited by: wastedfaith ]</small>