--Stumped-- Computer/Tranny
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--Stumped-- Computer/Tranny
HELP! I have a '93 F-150 XLT Flareside 4x4 with a 351W and an AOD-E tranny. This past weekend I pulled the motor out to replace the rear main seal, oil pump, water pump, starter, and a few gaskets. when I did this I had to disconnect all of my electrical connections including the battery. When I put the motor back in and started it up I got a check engine light that stays on. Also, my idle seems to be a little high and my tranny is shifting harder than before. I'm hoping that there is a way that I can reset my computer and fix these problems. I tried disconnecting the battery for a minute and hooking it back up but it didn't seem to do anything. The truck starts really easy and runs good. After about 5 seconds of running the check engine light kicks on. I also suspect a vaccum problem but I don't see why this would affect the tranny. If anybody knows what could be causing this please let me know.
Thanks in advance,
~Jason
Thanks in advance,
~Jason
Lead Driver
Joined: Feb 2003
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From: Oak Harbor, OH
In '93 behind a 351 it's an E4OD, not an AOD-E that was the 302 trans. It's more than likely a bad TPS, you said you know you have a vacuum leak, this will cause the high idle. Is the OD light blinking?
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well... I'm not positive about the vaccum leak... I'm just saying that it's possible... I did break one vaccum line but I fixed it already.
Also, the OD light is not blinking... the only light that is on is the check engine light
Also, the OD light is not blinking... the only light that is on is the check engine light
Lead Driver
Joined: Feb 2003
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From: Oak Harbor, OH
Pull the codes, that will tell you where to start. THe light is on because it detects a majpr malfunction of an emissions sensor. THe computer is going into limp mode and will destroy the catalytic converters if you let it run like that too long. The trans is shifting hard because the computer controls the pressure inside it. I'm thinking you have a vacuum leak at the map sensor, or EGR valve. The TPS or IAC may be causing issues too.
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alright. I'm going to get a code reader this weekend. Until then I'm going to recheck all of my Vaccum lines (including the one I fixed). I also have a spair IAC motor that I could throw on to make sure that is fine. I have no idea where the map sensor is... and as for the EGR valve and the TPS, I'll have to check these out
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Lead Driver
Joined: Feb 2003
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From: Oak Harbor, OH
The MAP sensor is on to of the heater box, or thereabouts. It has a three wire connector and a vacuum line going to it.
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Post Fiend
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From: Bonita Springs FL
Originally Posted by Flareside351
alright. I'm going to get a code reader this weekend. Until then I'm going to recheck all of my Vaccum lines (including the one I fixed). I also have a spair IAC motor that I could throw on to make sure that is fine. I have no idea where the map sensor is... and as for the EGR valve and the TPS, I'll have to check these out
Maybe you reconnected a vacuum line wrong - it's really easy to do.
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Yeah... I wasn't planning on actually buying a code reader... I normally just go to autozone... etc... and borrow one. I just stand in the parking lot and read my codes then hand them back their code reader... that lets me get my codes without paying any money... and then I don't have to be in the truck to see the codes.
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From: Calhoun GA
I'm going to say it is a vacuum leak and/or MAP sensor. I've seen a few (including mine) operate the way you describe and replacing/correcting these issues cured the problem.
Make sure the MAP sensor is plugged in, and double and triple check all vacuum connections.
Make sure the MAP sensor is plugged in, and double and triple check all vacuum connections.
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well, the truck's all better now... and of course it's due to a mistake on my part.
After giving the vaccum line/sensor hookups a good hard look I found that my TPS wasn't even hooked up. I must have completely missed it when putting the motor back in.
The wire was kinda hidden under my throttle body so I could barely see it.
Once I hooked it back up the check engine light stopped and the trucks shifting great now.
Thank you for all your help,
~Jason
After giving the vaccum line/sensor hookups a good hard look I found that my TPS wasn't even hooked up. I must have completely missed it when putting the motor back in.
The wire was kinda hidden under my throttle body so I could barely see it.
Once I hooked it back up the check engine light stopped and the trucks shifting great now.
Thank you for all your help,
~Jason