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Posted by 68_427_Fastback (Member # 1482) on :
 
What would make a 5.0L backfire in the intake, hesitate, jerk at low rpms and make the FP readjust itself? Its got a brand new FPR on it so its not a bad Regulator...
 
Posted by 68_427_Fastback (Member # 1482) on :
 
ttt
 
Posted by Cstang50 (Member # 4925) on :
 
what about the fuel pump? my frend had the same problem and it was the fuel pump

casey
 
Posted by EASTBAY5_0 (Member # 3292) on :
 
quote:
Originally posted by 68_427_Fastback:
What would make a 5.0L backfire in the intake, hesitate, jerk at low rpms and make the FP readjust itself? Its got a brand new FPR on it so its not a bad Regulator...
mine does the same thing also but only when getting low on fuel. it will pop thru the intake and slow to a crawl and then catch back up. could a small fuel leak cause this?
 
Posted by 68_427_Fastback (Member # 1482) on :
 
quote:
Originally posted by Cstang50:
what about the fuel pump? my frend had the same problem and it was the fuel pump

casey
I don't think so but i haven't checked it yet.
 
Posted by 68_427_Fastback (Member # 1482) on :
 
Backfiring in the intake means the car is running rich. What would cause the engine to run rich besides the oxygen sensors?
 
Posted by blind (Member # 3052) on :
 
stuck injectors or leaky injector o-rings, leaky /bad fuel pressure regulator, timing being off.

I had a really bad intake backfire last time I put my engine together and it blew the pvc valve about 30 feet [worship] [Big Grin] the timing was off.
 
Posted by 68_427_Fastback (Member # 1482) on :
 
could i install 19lb injectors without tuning it or changing the MAF?
 
Posted by 68_427_Fastback (Member # 1482) on :
 
ttt
 
Posted by blind (Member # 3052) on :
 
quote:
Originally posted by 68_427_Fastback:
could i install 19lb injectors without tuning it or changing the MAF?
19lb injectors are stock on the HO5.0 engines, so yes.
 
Posted by 68_427_Fastback (Member # 1482) on :
 
quote:
Originally posted by blind:
quote:
Originally posted by 68_427_Fastback:
could i install 19lb injectors without tuning it or changing the MAF?
19lb injectors are stock on the HO5.0 engines, so yes.
oh maybe i meant 24s.
 
Posted by Sprayin306 (Member # 6022) on :
 
Too lean or timing retarded too much causes popping in the intake. I don't know who you got too rich from.
 
Posted by HaulinAssMaro (Member # 541) on :
 
There are various reasons why it could be backfiring.Timing,Vacum Leak(s),Stretched Timing Chain or the timing chain could have skipped a tooth,Valve adj...I would check the timing and look for any vacum leaks to start off with.If that doesnt cure the problem than look into the other issues.Also you can only use the correct # injectors to what your mass air is calibrated for.
 
Posted by 68_427_Fastback (Member # 1482) on :
 
It runs perfect right when i start it up and the engine is cold. Then if i drive it for a while and the engine gets warm/hot it'll start hesitating and backfiring in the intake. I can smell gas really badly too when i come to stops.
 
Posted by BlownNOSMustang (Member # 158) on :
 
Plug wires or burnt spark boots, They will arc to groung when hot. A good start.
 
Posted by 68_427_Fastback (Member # 1482) on :
 
quote:
Originally posted by BlownNOSMustang:
Plug wires or burnt spark boots, They will arc to groung when hot. A good start.
i do hear a ticking like something is arcing but i've looked at it at night and can't see anything arcing i've had problems with my coil arcing before.
 
Posted by 68_427_Fastback (Member # 1482) on :
 
i advanced the timing to 13 degrees and it didn't backfire but it was hesitating really bad and i jumped out and opened the hood and the FP was t 20psi at idle [Frown] I think the fuel pump is going bad or something
 




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