I had a similar problem a while back , turned out to be the ignition pick up , not the magnetic sensors but the wheel it self. After checking everything , I noticed the little tab that sticks out from outer edge that signals the home trigger (I think ) was bent forward away from the sensor , after I streightened it out , like magic , everything went back to normal. Only thing is , at high RPM there was still a bit of breaking up and backfiring , I did some reading ( HALTECH manual) , and found out that the clearance between the sensor and the wheel is very critical , especially at high RPM,s , so I took the wheel off an got it as flat as I could , put it back on , then got a feeler gauge and got it as close to the sensor as possible without touching (of course) and I now hit 9000rpm with no sweat.

Thanks for all the replies...I understand that i must get the car tuned but there is no tuner here https://www.nopistons.com/forums/pub...O_DIR#>/11.gif ... i will try it myself..



What i am curious about is that when i turn the boost controller off and drive the car at 6.5 psi it runs great without any hesitation... But when i turn the boost controller on and add even 2% it starts hesitating ...I am confused why it starts as soon as the boost controller comes into the picture even if i am not increasing the boost significanlty.. may be .5 psi or something...



Will also check the ignition pick-up tomorrow.





thanks

Hi Guys,



OK here it goes... Whatif i just put the XS Single turbo map that i downloaded from the Forum... Considering that i am using a pretuned Powerfc which i ordered from a guy and asked him to tune it for 12psi for the twins.. Now the XS map should be better than what i am running now.. won't it??



I am asking because i don't have a Datalogit and i assume its easier to tune using the Datalogit... I will have to tune using my Commander... I think it will take the most of my weekend...



Also can a high Knock reading be whats cuasing the hesitation?? should i try turning off the Knock sensor?



Thanks for all your help.. but still more is needed... I am also thinking of getting a manual boost controller from a friend to check if the Profec-E01 is causing the problem.. because surprisingly even if i turn it on and increase the boost by only 2% the problem starts.. if i raise it further under pressure i hear the wastegate popping open...



thanks alot guys for all the help... I hope soon i can write to you guys saying Problem solved...

My first two thoughts were, wastegate, connected improperly maybe; and knock sensor. When I'm boosting 10PSI on my twins with my ProfecB SpecII and PMS piggyback, at higher RPM I hit a HARD fuel cut, but it I keep my foot in it, the boost will come back.. cut again, come back.. This problem has been attributed to the knock sensor, used in conjunction with the exhaust.. The knock sensor is 'listening' and getting resonance off the rotor housing and trips, cutting the fuel. Apparently relocating the knock sensor helps rectify the situation. The difference is, everyone says that a PFC solves this problem. This long explaination suggests that you read the knock sensor output on your PFC (if it has one) and see if this is cutting your fuel!

if you have high knock that might mean you're detontating, fix the detonation!

What do i check other than the engine? My knock sensor had high readings on the old engine and the engine before that...Car ran fine... i see 150+ on the commander...

How do i check the sensors if they r the reason? Also an update.. today when i was driving trying to boost more than 6.5psi the car made a loud noise and some exhaust gasket started leaking.. its making too much noise under the bonnet...else was all fine it was boosting till 6 psi i think i did'nt notice if it was holding boost or not.. but it is very loud... when i brought it home it seems like the gasket in between the manifold and turbo is gone...could that have been what was causing the problem.. i will give the car tomorrow to have a new gasket installed....



How do i check if i have a faulty sensor on the power Fc?? I read a post on the other forum titled "my car is what my tuner calls a problem child" this guy was having the same problem.. turned out to be a faulty water temp sensor... he said his old sensor gave feedback of 2.40v on the commander and another one that he used which fixed the problem gave feedback of 1.70v .... i don't know if i am checking the right screen but mine says .76v on the commander sensor check screen??



Please help and tell me where to locate the water temp senosr as i want to swap mine with a friends.. also where is a air temp sensor??



thanks

How do i check the sensors if they r the reason? Also an update.. today when i was driving trying to boost more than 6.5psi the car made a loud noise and some exhaust gasket started leaking.. its making too much noise under the bonnet...else was all fine it was boosting till 6 psi i think i did'nt notice if it was holding boost or not.. but it is very loud... when i brought it home it seems like the gasket in between the manifold and turbo is gone...could that have been what was causing the problem.. i will give the car tomorrow to have a new gasket installed....



How do i check if i have a faulty sensor on the power Fc?? I read a post on the other forum titled "my car is what my tuner calls a problem child" this guy was having the same problem.. turned out to be a faulty water temp sensor... he said his old sensor gave feedback of 2.40v on the commander and another one that he used which fixed the problem gave feedback of 1.70v .... i don't know if i am checking the right screen but mine says .76v on the commander sensor check screen??



Please help and tell me where to locate the water temp senosr as i want to swap mine with a friends.. also where is a air temp sensor??



thanks

Ok got the gasket installed.. during the process noticed one of the silicon hose from the intercooler pipe had a nasty cut... so i changed that too and thought to myself finally problem found and that i would be able to enjoy the car... But it became fine for 1 run and then i parked the car... 2 hours later i took the car out again same problem was there....



Ok one thing for sure the car is running rich.. even at the 4000rpms hesitation the A/F meter always reads rich.. Also after driving for a while if i park the car for a little while and then turn it back on it seems like its flooded... it starts right away but sounds like there is alot of fuel and the car seems like it wants to stall and then after 40 seconds to a minute it becomes ok...



Help help help... I think i thaw a tweety bird... oh man i am going bonkers...



Its 4:30 in the morning and i can hardly keep my eyes open.. still am browsing the forum to find a post with a similar problem...

Ok i think i did it....



When i started the car today the idle was like the car wanted to stall....



So i switched the car off to check what was wrong... i noticed on the power fc commander even with the car off.. it read +0.024 kg



even with the car off... when i start the car instead of going into negative it stays in positive... also fuel is being dumped from the exhuats... i thought it might be the map sensor... but it is hooked up..



Is it time for another rebuild??