Darius Juca

at first my probelm was mostly in 3rd and 4th at 3200rpm when boost starts kicking in, there would be a stumble and no performance or at least I did not dare push it....
NOW it idles funnly like it will stall or struggle while iddling and at a stoplight when I get going I have to rev the engine to 2k before I can engage the clutch and get going..allmost stalls and would probably If I would not push the clutch...this happons in all gears but not all the time..sometime it' idles and goes fine and sometimes I feel it will strand me..there is also a lot of popping...not too bad but very notible with the occasional louder pop...The engine also stalls/hesitates if I am in neutral and just rev it and definitelly sounds some times like it missfires...and it sounds different..weaker.....the funny thing is if I turn it off and start it again right when it's acting up I will be fine on restart..for a llittle bit.....I thought maybe a vacuum line? but now it seems more like ignition..and everythin in there except the DME is under 5K miles..I will check the fuel filter next..
Please help....any input much appreciated!!!

fast951

Check all the hoses. It sounds that you have a busted/cracked/loose hose. What's your fuel pressure, it should be around 3bars.. If your car has an Air Fuel gauge, report the readings.. Rich or Lean?

Quit driving the car till you figure out the problem. You should have a Bypass/shorting plug to replace the SMT5. Use the shorting plug see if it makes a difference.. Do you have the SMT5 or SMT6?

Email me directly and I'll assist you...

B951S

Whats the vaccum like at idle??,

Things that spring to mind are fuel pressure / pump / filter or maybe crank sensors.

Darius Juca

Hey thanks John I was thinking a vacuum, hose.....the pressure was at 48 psi but I turned it to 42 the autometer recorded slightly rich at idle but when gassed it would drop to lean but would stabilize back to stoich turning the fuel pressure I thought makes it run less rich..and yes I have the terminator plug....I have the smt5
would a hose explain the exhaust note change..I was thinkg misfire since it would also often pop in the exhaust..
You are probably right about the vacuum hose....once again Thank you.

Darius Juca

Whats the vaccum like at idle??,

Things that spring to mind are fuel pressure / pump / filter or maybe crank sen
B951s

pressure at the gauge is steady except when I rev it ..drops but then rises again......only thing in the fuel system that I am not sure of is the filter

How would I measure vacuum at idle?

B951S

If you have a boost gauge that measures idle that will tell you, otherwise most parts shops have vacuum gauges for diagnostics purposes. Handy having one as they can tell you a bunch.

Darius Juca

I have an autometer boost gauge..boost does not flutter but I could swear it should build boost quicker...of course once it begins to stumble I lift off...
I will go thru vacuum system and let you know the results..hope that willbe the culprit....

Claus Groth

Darius, a small vacuum leak will cause low idle and perhaps a little difficulty rolling from a stop but not your problem. You have a LARGE leak. When I had a similar problem, it was the turbocharger outlet hose. It had split along the back side, impossible to see until completely removed. The slit was normally closed and would open at higher intake pressures. If this is your problem, it it now getting worse, affecting idle and slow speed.

Good luck finding the problem.

Darius Juca

You seem to have nailed it!!!! ok time to hunt leaks....Rennlist brothers save my $$ again..lol.....John ,B951s and Clausyour quick and helpfull advice is much appreciated!!!!

nize

how about the tps ?

fast951

Darius, reset fuel pressure to 48-49psi. Your chips were setup for it. If you want to lean idle, do it with the SMT5.

Darius Juca

OOHh ok so 48 psi is good..I also wen to thru the vacuum lines and could not locate a leak......will look harder but also what I noticedis that the engigine when in neutral dies off idle if gassed and sounds off...only when it reaches about 2K it becomes more stable but still not right..
How could I check if the TPS is the problem?

nize

read this thread for the tps;
https://rennlist.com/forums/showthre...&highlight=tps

you can also check clark's garage;
http://www.clarks-garage.com/shop-manual/fuel-06.htm

Darius Juca

I checked the TPS not througly with continuiti meter becouse mine is kaputt but the TPS clicks and seems to be fine...but as nize said it could still be faulty....what would a clogged fuel filter be like..I am getting steady pressure and it drops for a spit second when I rev it but then goes right back up and stabilizes, back to hunting vacuum leaks....would a vacuum leak make my car misfire though???it misfires bad sometimes especially off idle or when I am at a stoplight and try to get going..misfires worst in 1st and 2nd....I am in a bad didnancial situatuon and would hate to buy a new TPS if not neededin idle when NOT in gear the car SOMETimes misfires and stumbles when reved off idle but once up in higher rpm it does fine..unless in gear and boost...

nize

what you describe sounds EXACTLY like the problems i had, which were fixed with a new TPS.