Won't accelerate
Won't accelerate
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Won't accelerate
1991 F-250, 5.8Land am having a problem with it running. Started out with it ocasionally dieing, but would start back up, a spark problemso the distributor was rebuilt. The motor would ping on acceleration, computer was holdint the timing advanced, replaced ECM. Error code said the TPS was not responding, replaced it. Now the engine runs fine until the temp. gauge comes up, then I cannot get power to accelerate. Push down on accelerater and the motor spits, sputters, dies, but still starts back up easily. Feul pressure is at 40, no codes. Any ideas?
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Joined: Mar 2014
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From: southern maryland
i hate to take hail marry chances but I'm feeling lucky tonight if you still have an egr valve momentarily disconnect it and see how it drives. to really diagnose it lets thingk spark air and fuel have you looked at your o2 sensors with the engine hot or done koer test.
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no accelaration
Yes, the EGR valve is still hooked up and not blocked off. Will try checking EGR and O2 testing tomorrow evening.Thanks for ideas.
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won't accelerate
OK, finally had a day yesterday to check out the truck. The book I am using is a chilton, checked out the O2 sensor and it checked good. Tried the EGR, tests good. Have been cleaning all grounds as I can fine them{ poor ground can cause strange events} Fuel pressure still runs steady at 38-40. Took it for a test drive this morning, and made it 1/2 mile before it acted up, won't accelerate agter the heat guage starts to move. The muffler is blown open due to backfiring during an earlier test run, could this be a problem? Noticed the gas gauge seems to be going down kind of fast, could it be flooding the intake? Am about to admit it is over my head{never ad mit defeat, a mechanic can fix anything, can't he} but truck won'trun the a repair shop.
Any other thoughts?
Tom
Any other thoughts?
Tom
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From: southern maryland
put a vacuum gauge on it. sounds like it could have an exhaust restriction. what were the 02 senors reading when you tested them(with the engine running bad). Have you checked your timing.
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vacuum reads at 19-20, jerk the throttle open a ways, vacuum drops to around 10 then back to 19 or 20 when idling. O2 sensor readings are 14V at poewr pin, ground pin shows good continuity, but could find no reading from sensor output posts. These readings were taken with engine ap to temp but in the driveway. Went for test drive, ran good for 1/2-3/4 mile then back to same problem, no power to accelarate. Thankfull for transfer case, low side lets me move with little power. O2 sensor sits between exhaust Y and is to hot to work and get accurate sensor readings, sorry.
Tom
Tom
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won't accelarate
Got the O2 sensor out, but threads must be messed up a little, the new sensor won't start in. What are the threads on the new sensor? A friend suggested to try the temp sensor, since it runs fine when cold. Ohm readings on the temp show OL regardless of the temperature, and they should change as the motor gets hotter, correct? Tom
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