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Hello Everyone ! After more research Im still at a loss And could use some help. First off I have no Codes, Setup is cai, new plugs, wire's, disty,(also tried old one), fuel pump, both new fuel filters, timing is at 13 degrees using 93 octane , new pcv, ground kit, header, new o2 sensor (Tested at 0.93 V) and full exhaust. also just tested tps.

: Problem is before engine is warm both under Full throttle and partial throttle the engine will lose power like the fuel is being cut off but does this randomly at no specific rpm or throttle posistion but seems to fade off over 5k rpm. This problem dose still persist when engine is warm but is less noticable. I have ran stp, and lucas fuel injectors through last 2 tanks, fuel economy has been down around 26 Mpg which is low considering i always shift under 3.5k usally under 2.8k rpms dont ride the clutch and drive gently, Most of the time . I have swapped out plugs wires and disty and still have had the same problem. One thing i should note is i did have the fuel injector wires cut at one point for old fuel injectors, Is it possible to hook them up backwards and still run ? also engine idles smooth could this possibly be fuel pressure regulator. Really need some idea to fix this problem im sure when i fix the fuel issue mpg will go up. Thanks in advanced !

This is a long-shot for you, but it happened to me. From washing my engine, I had pools of water built up in the spark plug wells. The plug wires were using this water to short directly to the block. Car stumbled like crazy, and I couldn't figure it out for a couple days.

Like I said, not very likely for you, but it happens.

im thinking your cat might be plugged.... i had the exact same problem so i cut my cat out and it was fine. and if you have the wires backwards on your injectors it shouldnt run since there should be a pulse from one wire ( ground i believe) and i believe the power wire wire stay constant.

I have actually done that myself while cleaning up my engine bay. But this problem has persisted for a lil over 5 months. Just cant seem to figure out what it is. Very frustrating.

One thing to add is every once and a while ill get a pop, sounds kinda like a backfire between shifts not very often though, i also smell exhaust from the engine bay while driving . cat Sounds like a very good possiblity. I think ill check it out on my day off. Any other ideas are very welcome. Thanks

95 rs wrote:im thinking your cat might be plugged.... i had the exact same problem so i cut my cat out and it was fine. and if you have the wires backwards on your injectors it shouldnt run since there should be a pulse from one wire ( ground i believe) and i believe the power wire wire stay constant.

+1. That was what I was going to reccomend!

Ok suprisingly the people who did my exhaust work never reinstalled the cat. and just stright piped it. so i have header, flex pipe, prescilencer and muffler . So now im really baffeled, What else could cause power surging ?

well then id say its almost sounding like a timing problem.... maybe get your timing checked? whens the last time you had the timing belt changed or off? it might be that... i really donno man i can ask at work tomorrow to our shop forman and see what he might think it is.

ModMX3 - (Carmaster2005) wrote:new o2 sensor (Tested at 0.93 V)

O2 sensor output (usually) should not be constant - it should oscillate between 0 and 1 very rapidly (after sufficiently warmed up of course). If you have warranty it wouldnt hurt to get a replacement....

Otherwise check the coolant temp sensor and burp the cooling system....

Ok After more searching around i relized that the egr port on the TB that was plugged off is now gone causing a major vacuume leak ! So now that I know what the problem is should I just replug it or run a line from the egr port to the intake tube between the maf and TB ? So the air would be metered ? Does the ECU enrich the fuel mixture when the egr is open ? Thank for everyones help.