Transmission just replaced, it works fine. Wife is driving car ('91Q), hits bump and engine kills. She is able to restart car but has problems with it stumbling.
I suspect fuel pump going out (pump has been noisy). I replace pump w/new OEM pump from Scottsdale. Still having problems w/stumbling. Car will start and idle. put it in drive and it will sometimes kill. Keep one foot on gas and one on brake to keep rpms up and it will not kill. Once you get moving it does ok, not great, will stumble sometimes and then you can nurse the gas pedal a little and it will clear up. You can go to WOT and it pulls real well w/only a slight hesitation, then it clears up and runs fine to redline, pulling hard all the way.
SO, what is the problem? Pump controller? Loose connection as a result of transmission replacement? Fuel filter? Fuel pressure regulator? Vaccuum leak?
If the pump controller is bad, does the pump not work at all. Is it possible for it to work on only two speeds and not on the other one (Example: Low and high speeds work, but not middle speed)?
:help
Pat
Transmission is fine, but a new problem now.
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Q451990
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Typically the controller will just fail, or will be intermittant, but not fail in just one mode...at least that's what I heard.
In my failure, it just failed all at once. What you're describing sounds a lot more like a bad MAF connection. Try wiggling the connector (and all of the others that you can find, especially the CAS!) and see if the idle speed changes. Any change indicates a bad connection.
If you want, pull the FPCU and check the solder joints on the board, and check the connector for evidence of overheating. You have to remove the back seat and rear package tray to get to the two 10MM bolts that hold it on.
Heath
In my failure, it just failed all at once. What you're describing sounds a lot more like a bad MAF connection. Try wiggling the connector (and all of the others that you can find, especially the CAS!) and see if the idle speed changes. Any change indicates a bad connection.
If you want, pull the FPCU and check the solder joints on the board, and check the connector for evidence of overheating. You have to remove the back seat and rear package tray to get to the two 10MM bolts that hold it on.
Heath
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GELLIS2586
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Check your injectors, check spark plugs/wires. My old 240 was doing that found i had a misfire from a sparkplug.
My friend has had the same problem on his avenger. Its only at idle and low rpm's right? We changed spark plugs and wires and a distributor cap and a new fuel pump. These helped but didn't completely solve the problem.
My friend has had the same problem on his avenger. Its only at idle and low rpm's right? We changed spark plugs and wires and a distributor cap and a new fuel pump. These helped but didn't completely solve the problem.
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Q45tech
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The path from the pump to the FPCU is common......one wire/connection goes to one place on the printed circuit board.This solder junction is the most common failure point.
There are failures of the transistors that act like variable resistors but they are rare and usually caused by alternator/regulator problems [voltage too high] or the solder point just happens to be very very robust compared to the average [it won't melt] and the worn pump motor starts drawing double the design current because it is turning so slow.
If members would just measure the idle pump current they would know when it is getting too late...........assuming they can put up with the pump noise.
Dash mounted pump ammeter or 30 day checks...........the pump after all has to be changed but saving the $500 FPCU is the ideal
There are failures of the transistors that act like variable resistors but they are rare and usually caused by alternator/regulator problems [voltage too high] or the solder point just happens to be very very robust compared to the average [it won't melt] and the worn pump motor starts drawing double the design current because it is turning so slow.
If members would just measure the idle pump current they would know when it is getting too late...........assuming they can put up with the pump noise.
Dash mounted pump ammeter or 30 day checks...........the pump after all has to be changed but saving the $500 FPCU is the ideal
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elwesso
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Will the controller fail AFTER a new pump has been installed.....
For instance, on July of 02, the previous owner took the car in for a hard start condition when it was hot.... Turned out the fuel filter was THAT clogged...... Dealer recommends new fuel pump and controller, but the dealer just replaces the filter...... About 5 months later, the pump died, and the owner replaced the pump....... Is the controller possibly toast???
For instance, on July of 02, the previous owner took the car in for a hard start condition when it was hot.... Turned out the fuel filter was THAT clogged...... Dealer recommends new fuel pump and controller, but the dealer just replaces the filter...... About 5 months later, the pump died, and the owner replaced the pump....... Is the controller possibly toast???