WTF could this be now?

some of you probably saw my thread about me using a fram fuel filter and my car started hesitating really badly.

i swapped it for the motorsport filter, and the car was fine. or so i thought. today a friend stopped by, and i took him for a ride in the car. when i swapped the filter, i gave the car about 1/4 throttle and it boosted a little and no problems. with the fram the same conditions caused problems.

so i thought it was fixed. today i gave it about 1/2 throttle, it boosted for a second, didnt feel like it was pulling as hard as normal, so i was letting off. in that split second all this was happening it cutout before i let off. same bs over again.

motorsport filter brand new. car drives normally, just cuts out and loses fuel pressure when its boosting. no problems at all before i changed my filter. im lost, any suggestions from here?

What are your mods?

Is the car dropping boost on it's own? Because there could be another problem if it is. Those filters are one way filters and can't be screwed up. You could be blowing spark out as well, what are your plugs gapped at?

mods are 2.93, rwtd tune, k&n fipk, magnaflow catback. thats it. really safe tune, 19 degree's timing.

stock untouched plugs. whenever i apply enough throttle for the car to boost (second pump engaging) it drops fuel pressure. went from mid 40's to low 30's the last time i datalogged it.

only thing i touched when this occured, was an oil change and the fuel filter. filters flow arrow is POINTING towards the drivers side of the car. which i believe is where i followed the line to. can anyone off the top of their head recall thats wrong?

not sure what else could be causing this, it seems to be an issue with the fuel obviously since i changed the filter. im going to return the car to stock and see if this issue goes away. i had been planning to do it anyway, so this will motivate me to do it faster.

i know when I put my 2.93 on, I grabbed a new set of NGK's and gapped them smaller properly.

Hey 88sc gt-- was that your black cobra parked at costco in tumwater on friday?

nah wasnt me at costco.

You might want to double check your fuel filter install to this How To with pics.

http://www.svtperformance.com/forums/showthread.php?t=260804&highlight=Fram

Oh, and remember that you probably disconnected the battery. It takes a few hours for the computer to "relearn". I suppose it is remotely possible that if you did disconnect the battery/reconnect the battery that during that time an issue could temporarily develop. You might want to give it a day or two before trying anything else. Especially if you did nothing but change the filter.

You said you found the filter full of crap in your other thread. I mentioned to you then how important I thought it was to find out what that was and where it came from. It's even more important now that you continue to have the problem. I'm wondering if you aren't having a pump or some other related hardware coming apart. Take the fuel filter back off and check it for debris. I would even go so far as to cut it open and inspect it. Be careful not to cut it with something that will generate sparks.

By the way, the arrow goes in the direction of fuel flow.

i dont recall saying i found it full of stuff, maybe your mixing me up? i only replaced this as preventative maintance if i did indicate something like that. car has 14k miles, i was doing it just shy of 15k like most people do.

anyway, its pointing the right direction, i know the arrow goes with the fuel lol. only reason i mentioned it was pointing towards drivers side, is i wondered if i got my perception mixed up laying on my back then reaching up and put it on wrong.

thanks for the link bob, but honestly its a simple swap. fuel lines clicked back on, no leaks, brand new filter, pn same as stock one. fuel came out really clean from my stock filter, so it probably didnt even need it.

ive talked to a bunch of people. it doesnt make sense to them. so its either a fuel pump issue or my plugs. going to pull a plug tonight and check it out. local parts store has tr-6's incase i need new ones.

It almost sounds like a bad FRPS.
You might want to check it.

someone suggested that to me last night. smelled the dipstick and theres no scent of gas that i can tell. i pulled a plug, will post some pics, they appear plenty normal to me though.

here are two pics of the plug i pulled. drivers side, first plug

gap was about 42 on it.





flash changed the tone of it somewhat.

I believe if you pull the vacuum line off and run the car this should tell you if it's the problem. I had the same problem as you. That was my problem. You may have a small hole in the rubber diaphram and it only effects higher throttle applications.

If the sensor is bad, it will send wierd signals to the PCU causing sporatic running problems.

which line do i pull? im not real familiar with this engine setup.

only thing i was told to do was smell the dipstick for gas. ill pull whatever line off and check once i know which it is.

I'll see if I can find a pic.

thanks man, appreciate it.

Here you go.
Pull off the vacuum line and take it for a ride. I believe if it is the FRPS it shoud run a lot better.

awesome. ill give it a shot.

back once the car warms up and i drop the foot :bash:

I think you need to plug the line so there won't be a vacuum leak.
Good Luck!