Engine impairment.
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Joined: Jan 2007
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Thanks guys,
I only said those other sensors because I might not need them, but it definetly wouldn't hurt. Oil pressure and temp im not sure that they are that accurate. O2 prolly has never been changed. I'm all for replacing things so that I know whats working. If the oil pressure is low, I know that the gauge works, and so forth. I completely rebuilt the 302 from an 86 Bronco a few years ago. Did the whole 9 yards, rebuild, clean engine bay(you coulda eaten off it) and painted the engine ford blue and gray. was very nice for my first rebuild. Little did I know, the temp gauge was not accurate and 2 weeks later the upper radiator hose busted and I didn't know until it was too late. Attempting to prevent any tragedies such as that.
I only said those other sensors because I might not need them, but it definetly wouldn't hurt. Oil pressure and temp im not sure that they are that accurate. O2 prolly has never been changed. I'm all for replacing things so that I know whats working. If the oil pressure is low, I know that the gauge works, and so forth. I completely rebuilt the 302 from an 86 Bronco a few years ago. Did the whole 9 yards, rebuild, clean engine bay(you coulda eaten off it) and painted the engine ford blue and gray. was very nice for my first rebuild. Little did I know, the temp gauge was not accurate and 2 weeks later the upper radiator hose busted and I didn't know until it was too late. Attempting to prevent any tragedies such as that.
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That is true, maybe I'll rephrase that and say I plan on getting those soon. First thing is first, gotta get it running correctly. It gets dark to early to work on it after I get home. Satuday will be the first day I can really start on the above mentioned things. And its supposed to be something like highs in the 30's! The bronco may get pushed back till the sun wants to show up.
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Ok,
I changed out the TPS and the truck runs better. It doesn't stall or anything, revs up nice and smooth. However, when I tried to drive it, it loses all power about 2500 rpms. This has totally thrown me off, I thought it was my 4wd sticking at first, but my 4wd doesn't even work on its own. I ran codes again and got 121 and 128. TPS voltage is too high? How? Sensor is new. And map sensor vacume too low? Where is the map sensor and why did it go bad?
I changed out the TPS and the truck runs better. It doesn't stall or anything, revs up nice and smooth. However, when I tried to drive it, it loses all power about 2500 rpms. This has totally thrown me off, I thought it was my 4wd sticking at first, but my 4wd doesn't even work on its own. I ran codes again and got 121 and 128. TPS voltage is too high? How? Sensor is new. And map sensor vacume too low? Where is the map sensor and why did it go bad?
Lead Driver
Joined: Sep 2002
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From: Gateway to the West
TPS voltage can be too high if it is mis-aligned If memory serves it needs to be 0VDC at WOT. It then gains VREF as the throttle plates close.
MAP sensor (Manifold Absolute Pressure) monitors air pressure inside the intake manifold and works in conjunction with the PCM and ICM to control spark timing. It's mounted to the firewall near the passenger side top of the engine. It has both vacuum and electrical connections. This is probably as simply as a vacuum leak from a worn out hose.
MAP sensor (Manifold Absolute Pressure) monitors air pressure inside the intake manifold and works in conjunction with the PCM and ICM to control spark timing. It's mounted to the firewall near the passenger side top of the engine. It has both vacuum and electrical connections. This is probably as simply as a vacuum leak from a worn out hose.
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Alright thanks for all the help, truck is running very good now. I'm embarassed to say what the problem was, but I'm gonna do it anyway. The TPS had a sticky ring around the hole, and I thought this was to seal the TPS. Evidently, this was to go on the bottom. So, Once the TPS was put on correctly, problem solved. DER!!! I'm so special
Hotshot
Joined: Jul 2002
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From: Bend,OR
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94' Bronco 5L > Flat spot when accelerating - easiest way to check TPS ?
1994 Ford Bronco 5L with a flat spot when accelerating, only if slow on the throttle. When I push throttle all the way down, it then jumps past the flat spot and accelerates fine. Accelerates fine when in park only notice while driving. Have replaced fuel filter, cap & rotor. Need to get through emissions and hoping to not have to spend a lot. Planing to sell or trade in for another vehicle. Any assistance would be greatly appreciated!!!
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