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couple of ????

elkarcher

Bronco Guru
Joined
Dec 19, 2003
Messages
1,429
First start of the day, when i fire my rig up it dies. It takes about 3-4 times to start it before it stays running. After it stays running if i give it some gas it bogs down and just about dies. backfires through the intake. After idleing for about 5-6 min runs fine, no back fire or boging out.

#2. when its cold and idling if i hold the brake the damn thing about dies. Let off and its fine. Bad booster im thinking.

On the centech harness what it the RED wire labeled RETURN for. I did not see anything on it in the instruction manual. Driverside of the harness.

sorry so many questions.

Thanks Tim


92 Mustang EFI/ RJM harness Centech body harness.
 
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Skiddy

Bronco Guru
Joined
Oct 8, 2003
Messages
11,557
First start of the day, when i fire my rig up it dies. It takes about 3-4 times to start it before it stays running. After it stays running if i give it some gas it boogs down and just about dies. backfires through the intake. After idleing for about 5-6 min runs fine, no back fire or booging out.
mine is doing that right now not just when cold, just haven't checked into it yet. i also have an injector staying open so i need to fix that first
Have you checked any codes?
 

dbevans2249

Sr. Member
Joined
Sep 21, 2003
Messages
610
Loc.
Buena Park, Ca.
IIRC that Red Wire is for the wipers. I think it powers them to the park position. Sorry if I am wrong, going from memory as my centek instructions are in Alta Clifornia and I am in Baja.
 
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elkarcher

Bronco Guru
Joined
Dec 19, 2003
Messages
1,429
mine is doing that right now not just when cold, just haven't checked into it yet. i also have an injector staying open so i need to fix that first
Have you checked any codes?

Cant check codes yet. Need to hook up a light. That would help greatly.
 
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elkarcher

Bronco Guru
Joined
Dec 19, 2003
Messages
1,429
IIRC that Red Wire is for the wipers. I think it powers them to the park position. Sorry if I am wrong, going from memory as my centek instructions are in Alta Clifornia and I am in Baja.

thanks thats where it goes.
 
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Pedestrian

Bronco Missionary
Joined
Sep 10, 2008
Messages
2,299
Gotta run codes, just use a test light for now.

IAT could be way off, ECT could be way off.
Weak fuel pressure. Vacuum leak. Leaking injector/s
 
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elkarcher

Bronco Guru
Joined
Dec 19, 2003
Messages
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OK just got done with the codes. Here we go #22 MAP/BP sensor, #51 coolant temp sensor, 53 Throttle position , and 54 ACT air charge senser. Not really sure where to start. My guess is the map/TPS senor. I have tested the TPS and i have about 4.5v at idle. I should have about 1v right. Am i going the right direction or way off.

Thanks Tim
 
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elkarcher

Bronco Guru
Joined
Dec 19, 2003
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1,429
Thats what i thought so I am going to change it out and see if that helps. I have read FFI and 1v is where it needs to be.

Thanks
 
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elkarcher

Bronco Guru
Joined
Dec 19, 2003
Messages
1,429
changed the TPS and no change. got 1v now but the hesitation has not gone away. here are the codes i just pulled. 51 22 53 547 81 82. Hope i dont have to live with this. All the sensors are coming up good according to RJM's tech data.
 
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elkarcher

Bronco Guru
Joined
Dec 19, 2003
Messages
1,429
Ok so i got the new brake booster and I still have the same issue. The rig starts up and dies. It does this for a few times and then finally stays running. After about 10 minutes of idling it runs great. If I dont let it warm up is back fires, and runs like crap. I have checked codes and air leaks and nothing. Not sure what the hell is going on. Any help would be great.

Thanks Tim
 
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elkarcher

Bronco Guru
Joined
Dec 19, 2003
Messages
1,429
Still having the same issues with the same codes, not sure what else to do. Anyone have some ideas. I have tried everything I can think of.

Tim
 
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elkarcher

Bronco Guru
Joined
Dec 19, 2003
Messages
1,429
could a bad O2 sensor cause this condition. No code for it but ya never know
 

EFI Guy

Sponsor/Vendor
TheEFIguy@gmail
Joined
Apr 14, 2013
Messages
1,049
Loc.
BFE
Just going off of memory all of those sensors share the sig return circuit. When you are pulling codes are you doing it with the sig return or using ground?

The reason I ask is because there are several ways to fry the sig return inside the PCM. It's actually pretty common to see them burnt up now days.

If you're able to pull codes using the sig return instead of ground it should be ok. I hate to say it, but it might be time to crack that PCM open and look for the burnt trace.
 
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elkarcher

Bronco Guru
Joined
Dec 19, 2003
Messages
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using the sig return, I do have another computer so i might try that and see if that changes things.
 
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