Car falls on its face after 5K 6psi...

[one320b]

I've about had it w/ this car,lol... I've had it for two years, since brand new...it has 92,xxx miles on it now. It's an '03 ES that I boosted at about 65K miles... it ran fine for about 20K miles...but it developed a hesitation, I could barely floor the car or even give it gas w/out it misfiring...some new NGK colder plugs SEEMED to fix that problem...it was night and day...the car ran great...but NOW if I floor the car..go to 6psi around 4500 to 5K + it feels like its slowing down...I can even here a little misfire(today for the first time i could hear it sputtering from the exhaust)...I'm running 10.1 to 11.1AFRs on a day to day basis...6psi in 5th gear is 10.1...if I let off and hit it again...it gets better then gets worse again. It's so frustrating...it feels like it's losing fuel, but the AFRs don't drop...I have one bad plug wire that I know is bad from the dyno(got a nice shock when hooking up the rpm signal wire for the dynojet).. it cant be fuel, it may still be ignition..but it's only 6psi...wtf..anybody got some ideas? it holds 6psi fine btw...

 

[ddogg777]

I missed where you said what you're using to control fuel and timing...

 

[Pretzellogic]

I missed where you said what you're using to control fuel and timing...

(evil)

 

[Dexter]

bad FM clamp?

 

[one320b]

Holy crap...you guys are quick w/ the responses arent u! I know I'll get bashed, but it is the stock ECU...FM clamp, larger fuel pump, FMU, FMIC, Garrett BB turbo...its a custom kit w/ mazdacomp manifold...like I said it was all working fine for about 20K miles... I'm leaning towards bad FM clamp...but have they been known to "go bad" or are they just "bad" ...I used it for a while w/ no problems....

If I decide to keep going w/ this car...it'll get a standalone treatment...I've got an rx7 as well that I've built completely w/ standalone and love it..but this my first piston/open-close loop ecu combo..and I've hated it...tuning is so much nicer on an rx7,lol...

 

[Dexter]

i knew it was FM clamp...its probably bad. they have been known to go bad, for whatever reason

 

[one320b]

Would a better alternative be the MPI tuner??

The only reason I still don't feel that the FM Clamp is bad...is it holds a steady AFR all the way to where it bogs/sputters... of course it changes cuz I take my foot off the gas..its got 92K miles,lol..I'm not trying to push my luck TOOOO much. I'm already trying to make arrangements to get a new motor as I know mine can't last too much longer... I was really hoping to move up to 8psi this weekend too...

 

[Dexter]

there is a way to test it, im not sure, ive never had one...but do a seach on here for bad FM clamp or something.

Haltech, Microtech are standalones im sure you heard of that you can run in parallel with the stock ecu

some people use "MPI tuner", eManage or "DSMConvert AFC" as piggybacks.

 

[Matthew]

you can send the clamp back to fm takes them a few days to test. how old is/was it? there was a bad batch for awhile

 

[one320b]

I got the clamp back in december I believe... so its a little old, but not that bad...

I used microtech on my rx7, liked it ..but had to ditch it for a tec3 that was better suited for my needs... anybody running a tec3 unit? Just curious...

I'll have to see where funds are and evaluate what I really want to do w/ this car... I appreciate your alls input... I'll keep you posted if I find anything else..

 

[Matthew]

sounds like when i got mine (the bad one). what were you using to monitor AFRs?

 

[ddogg777]

Yep, definitely the Clamp... Good work guys.

 

[igdrasil]

You are going pig rich on open loop. You should check:
1. FM wiring,
2. O2 sensor
3. Boost leak (could be, MAF sensing a lot of air and leaking elsewhere)
4. MAF (check if its broken or has something blocking the entrance)

 

[one320b]

Well my MAF is still a possibility just due to the fact that it's on the pressure side and has 90K+ miles on it,lol...nothing is blocking the path. Two of my couplers are on the outs (they weren't nylong, they were standard rubber used for CAI, etc). I just installed my turbo timer a few days ago and checked the wiring for the FM clamp while I was in there and it all seems to be good..so that rules that out. o2 sensor is old as well ...so maybe it's due for replacement? The car also smokes(not a lot) during hard acceleration...but it's not a black fuel smoke its more like a gray....similar smell to clutch burning... I've got some things to work out I guess...if it's running too rich at 6psi, maybe it just needs 8psi to lean it out,lol....

 

[igdrasil]

you should clean the MAF it gets very dirty on pressure side, you should also clean the intercooler and piping once.

 

[one320b]

I've cleaned the MAF before when I was having really bad ignition problems...it wasn't THAT dirty..but it helped. I'm still weighing my options ..i'd like to get another rx7, but I also want to keep my gas mileage that the protege offers...decisions decisions..

 

[jeffmsp]

what kind of exhaust are you running? the smoke and smell could be from a failing head gasket.

 

[one320b]

It's a custom exhaust I built myself ...basically mandrel 2" downpipe to stock gutted cats/stock pipes/apexi n1 muffler...only two gaskets in the entire system... if the gasket was failing ..I would imagine I'd have a leak by now as the car has been smoking for about a month... I'll look into it though, thanks for the suggestion...