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Discussion Starter · #1 ·
Hey guys looking for some clues on this one. The car will run for right at 5 minutes and sputter a little and quit.
The plugs will be wet with gas afterwards. I pulled the fuel line off of the top of the filter to check if it was getting fuel and it started right back up, and gas came out of the top of the filter so it is getting gas.
I put the line back on and tried to start it again and it wouldn't. Took it back off... and it started.
I swapped the pressure regulator with another one that I had on an engine sitting in the garage and it still does the same thing.
Not sure where to go with this one except checking to see if the return is pinched somewhere under the car.
I did put this engine in the car though and it is rebuilt but I dont think that has anything to do with the issues that its having.
One other question, does anyone have a vacuum routing diagram for a California spec car? Just curious about this one and would like to double check all of my routing.
thanks..
 

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Look under the front of the hood for a drawing of the vacuum hoses.

Do you have the right vacuum hose connected to the pressure regulator?

Find the small plastic box labeled "Diagnostic" attached to the passengers side shock tower. Use a section of electrical wire to jump the B+ and FP terminals, tis turn will pump on with the ign switch. Determine if the engine now runs longer then 5 minutes. If so there be an issue with the fuel pump circuits.
 

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Discussion Starter · #3 ·
Thats funny about the vacuum routing diagram under the hood. I guess I didn't see that because the hood is sitting on top of the car and I just didn't look at it before I took it off. I'll check it out in a few. Not sure if its the right hose or not!
I also have to wait a while before I can start it back. It will never start right back up. Not sure how long I have to wait though.
 

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'93 LE Wagon V6 '94 LE I4
'93 V6 wagon, '94 I4
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OP,
Are you getting spark when the vehicle fails to start? Have you checked out the coil? You mentioned that the car runs until it warms up, then quits. This type of problem is often ignition related.
 

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sound like it might be engine coolant temperater sensor malfunction, i had this problem a few years ago, only able to start cold engine, once warm up, or after driving on highway, either have to keep the foot on the gas pedal, or it will die, sometime able to start, sometime have to wait until engine cool down.
i also seen similar problem being caued by a vacuum leak.
 

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Discussion Starter · #6 ·
I did put a new distributor and coil in it the other day because I was sure that was it but it didn't work. I was stupid and didn't check the spark before getting those items. It tries to start but just won't.
 

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Ninja wrench anywhere
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Hey guys looking for some clues on this one. The car will run for right at 5 minutes and sputter a little and quit.
The plugs will be wet with gas afterwards. I pulled the fuel line off of the top of the filter to check if it was getting fuel and it started right back up, and gas came out of the top of the filter so it is getting gas.
I put the line back on and tried to start it again and it wouldn't. Took it back off... and it started.
I swapped the pressure regulator with another one that I had on an engine sitting in the garage and it still does the same thing.
Not sure where to go with this one except checking to see if the return is pinched somewhere under the car.
I did put this engine in the car though and it is rebuilt but I dont think that has anything to do with the issues that its having.
One other question, does anyone have a vacuum routing diagram for a California spec car? Just curious about this one and would like to double check all of my routing.
thanks..
I assume that you have this "dieing" problem as long as the engine is warmed up? What happens if you give 'er some throttle or disconnect the intake hose from the throttle body?

Sounds like she's getting plenty of fuel (frankly, she sounds flooded) and spark. That leaves air. Since it happens after the coolant warms up (i.e., the computer thinks it's OK to go into closed-loop mode) I'd be looking at the sensors that tell the rig how much airflow you're getting -- the MAP sensor first, then the Throttle Position Sensor. Caveat: frankly the symptoms aren't quite right for either of those to be hosed, but it sure sounds like an insufficent air / way too much fuel sort of situation. I'm trying to think of a situation where the O2 sensor is broken (i.e., continually reading "lean") that would show these symptoms, but I don't think it's possible for the O2 sensor to screw up the mixture this badly. It just really sounds like way too little air is getting into the throttle body, and the computer doesn't know it.
 

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Discussion Starter · #8 ·
During the few minutes that it is running when I give it throttle it will hesitate a little just above idle, which is in the warm up stage still (1200rpm give or take 100) and then smooth out and rev pretty normal.
While taking the fuel line off of the top of the filter I did leave the hose off of the throttle body when I started it and it just sucked air. I couldn't let it run but a few seconds as it started pouring fuel out of the top of the filter.
 

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Discussion Starter · #9 ·
Look under the front of the hood for a drawing of the vacuum hoses.

Do you have the right vacuum hose connected to the pressure regulator?

Find the small plastic box labeled "Diagnostic" attached to the passengers side shock tower. Use a section of electrical wire to jump the B+ and FP terminals, tis turn will pump on with the ign switch. Determine if the engine now runs longer then 5 minutes. If so there be an issue with the fuel pump circuits.

I made sure all the vacuum stuff was correct according to the diagram under the hood and it is.
Also ran the jumper wire from the B+ to FP terminals and like clockwork, it quit at 5 minutes.
 

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Being time dependant, I'm thinking something electronic, like an output circuit in the ECM.
But the fuel line off deal? That does sound like the temp sensor, did you check it?
 

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Discussion Starter · #11 ·
Being time dependant, I'm thinking something electronic, like an output circuit in the ECM.
But the fuel line off deal? That does sound like the temp sensor, did you check it?
I think the temp sensor is about the only thing I haven't checked. I'll try it tomorrow and post what the outcome is.
 

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Discussion Starter · #12 ·
Well I found the problem! It was the ECT sensor. I put one on there that I got off of a Camry in a junk yard and it started and ran for a full 10 minutes and didn't quit till I turned it off. But it starrted back up a few times in a row. Seemed like it ran a little smoother the whole time too. I bought this car knowing it needed a motor but other problems that it had I was unaware of until i got the motor in. Thanks to everyone for all the suggestions on what to try.
 

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Well I found the problem! It was the ECT sensor. I put one on there that I got off of a Camry in a junk yard and it started and ran for a full 10 minutes and didn't quit till I turned it off. But it starrted back up a few times in a row. Seemed like it ran a little smoother the whole time too. I bought this car knowing it needed a motor but other problems that it had I was unaware of until i got the motor in. Thanks to everyone for all the suggestions on what to try.
Kudos to those suggesting the coolant temperature sensor! Just curious -- are you set up to test the ECT (procedure at http://www.camrystuff.com/manuals/Gen3/eg1.pdf page EG1-219)? I'm curious what sort of failure mode of the ECT would cause the engine to die after warmup...
 

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Discussion Starter · #14 ·
I didn't test it, just kindof figured that it was about the only thing left that I hadn't checked. Should have checked it first. I didn't think the engine had ever fully warmed up when it quit running, guess thats one of the main reasons I hadn't checked it. It didn't give me a code either.
 

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I didn't test it, just kindof figured that it was about the only thing left that I hadn't checked. Should have checked it first. I didn't think the engine had ever fully warmed up when it quit running, guess thats one of the main reasons I hadn't checked it. It didn't give me a code either.
Bummer -- I've heard a few accounts of defective coolant temp sensors causing engines to die, but I've never had a chance to get my hands on an ECT that had caused the problem...I've always wondered what the failure mode was...doesn't seem like a simple open or short would give the symptoms, and a simple open/short should throw a DTC 22, anywho.
 

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Kudos to those suggesting the coolant temperature sensor! Just curious -- are you set up to test the ECT (procedure at http://www.camrystuff.com/manuals/Gen3/eg1.pdf page EG1-219)? I'm curious what sort of failure mode of the ECT would cause the engine to die after warmup...

i paid very expensive repairs at toyota dealer when my 93 has was dying like what described here on this discussion, the technicians at dealer don't know what the cause, and just swap parts at my expense, until i told them i did research on web and suggest check Engine coolant temperature sensor.
cost and benefit equation doesn't add up on long term repair,
that was how i started to read factory service manual, and do my own repair.

anyway, from i understand, when starting a cold engine, the ecu is program to give more gas on its own to rev RPM higher, so the engine can warm quicker. after about 4 to 5 minutes, when the engine has reach optimal engine temperature, the ECT will tell the ECU to cut back on gas, but since it is malfunction, the ECU doesn't know and still thinking the engine is cold, and keep pumping gas, thus, floods and stalls the engine, like i said earlier, if you keep the foot on gas pedal to open the throttle, it will stay running to compensate the extra gas.

it is a common gen3 4cyl problem, i've seem quite a few TN people has this problem.
 

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Hmmm. I think I'll try popping off the ECT connector on my 95 and sub in a 2K resistor -- that should make the ECM think the coolant's still at room temperature. The results should be instructive. Oh, and sorry for the thread drift, OP.
 

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Hmmm. I think I'll try popping off the ECT connector on my 95 and sub in a 2K resistor -- that should make the ECM think the coolant's still at room temperature. The results should be instructive. Oh, and sorry for the thread drift, OP.
Played around with the rig off and on tonight. A 2K resistor caused a somewhat high (1500rpm) idle, and a somewhat rich-smelling exhaust, but otherwise ran OK even when warmed up.

A 10K resistor (equivalent to sub-zero for the ECT), would start from cold, but idle quite high (2000+ rpm), with very rich exhaust (damned near gagged me, even parked in the driveway). Wouldn't run or start anywhere near a warmed up condition. Sounds similar to the OP's situation.

For giggles, I also left the ECT connector disconnected for bit. As you'd expect, I immediately got a CEL with a DTC 22. Gotta love it when things work like the manual sez :D .

This has been neat thread -- I hadn't realized exactly how much the ECT influenced the mixture setting.
 
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