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Discussion Starter #1
my baby's been down and out for a while now. haven't had time so i took it to a shop. payed $225 for them to do practically nothing. they replaced my spark plugs and dizzy cap (both of which were brand new, and i tolled them specifically not to replace anything without contacting me first.) they directly ran a can of high concentrated injector cleaner through the fuel rail and it finally stayed running after that, barely, but at least its running. it sputters and bogs with no power whatsoever. stalls all the time, you get the idea.
At first, when they had just replaced the spark plugs it stayed running for about a half minute, then apparently the engine was getting way to much fuel and just flooded the hell out of itself.
my best guess is that it had such a hard time starting because of the cold start injectors were putting in too much fuel in combination with the injectors leaking?
im doing a compression test tomorrow, i've tested the spark in the number one spark plug and its getting good spark, ill check the rest tomorrow aswell.

what do you guys think? im ready to just buy the brand new injectors and hope for the best.
 

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You assume too much.

When and how did the problem develop?

Did the car sit for any ammount of time, or did it just start doing this one day?

I've seen a hundred people on this forum blame their cold start injectors, and I've seen 99 of those end up being entirely false.

You need three things for a car to run correctly.
1: Compression, enough of it and at the right time.
2: Fuel, pressure and injector timing are the only variables.
3: Spark, happening at the electrode and at the right time.

Give me the run-down on when and how the car started running poorly, and we'll diagnose from there.

--billyM
 

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Discussion Starter #3
now thats what im looking for ;)
the problem started a few months after i swapped my junked 5m for a junkyard 5m. the junkyard motor had 150 compression consistantly throughout the six cylinders when i did the compression test after the first test drive. it ran beatifully, and i even got better times with it.
after a few months the car began to idle rough when i would start it, and idle very low. very gradually the problem got worse and the odd time it would stall when i would let the rpms drop on there own, after the car would completely warm up.
The car did sit for a good 3/4 year, so when the problem started I changed the fuel filter, and that didn't help a bit. the dizzy cap, router, plugs, and wires have all been replaced.
the car became too unreliable to drive everyday so i parked it. a few weeks later i tried to start it and it wouldn't run longer than 5 seconds at a very low idle.
i sprayed carb cleaner into the throttle body and cleaned the inside a bit with a toothbrush, a pretty stupid stab at fixing the problem but whatever.
I believe the problem started with the old 5m, very rarely when i would start it right after it had completely warmed up it would idle very low for about ten seconds, but straighten out after that. when i did the swap i transfered all the stuff from the old motor to the "new" one because the junkyard spliced the wireing harness on the motor. so if that was the initial start of the problem, it would have something to do with all the old motors parts?
I advanced the dizzy timing almost all the way because that was the only way i could get the car to run half assed.
nobody i have brought the car to can give me any pointers. any advice/help is greatly appreciated.
-Jack
 

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I would go to the TSRM to the section on diagnosis by symptom and I would check each thing one by one. Have you checked the coil or the pickup in the distributor? You'll need a volt/ohm/multimeter to check a lot of things, and also, check for air leaks between the AFM and the throttle body.

Go to page 8 of the following link. It's for an '82 Supra, there are some differences between '82 and '84 but this would be a good checklist of things to check out before blindly replacing parts. If you search, there is a TSRM for later years.

http://www.sfmodelaclub.org/user/1982 Emissions Repair Manual 5M-GE.pdf

It's really frustrating to have something like this come up that isn't simple to diagnose and fix.
 

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Have you checked the fuel pump?
 

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Yeah, reading those symptoms, my first guess is that you have a fuel delivery problem. The fuel pump may be worn out and providing low pressure and flow. The fuel pump may also be partially plugged up. Maybe you have a bunch of dirt in the fuel tank? A kinked or clogged fuel line? That's where I'd start looking.

Running for a minute and sputtering slowly to a stop doesn't sound like an ignition or engine mechanical problem.
 

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Discussion Starter #7
i fixed it today... finally, turned out to be something so stupid, i just finally got the time to take a look at it myself. the fu#$ing timing belt skipped. it must have skipped one notch first, then one more, that would explain why it gradually got worse, combined with my injectors needing a little bit of cleaning. I can't believe i didn't think of that... having to advance the dizzy timing should have clued me in.
thanks for your time guys
 
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