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viper11
07-15-2006, 06:11 AM
hi guys
i finally got my car back from the exhaust guy and he did a good job with the space constraints
so now im trying to tune it to run, at the moment the intercooler is not hooked up so i can tune the efi without boost to pass air-care/smog test
the problem :- the car is running rich and it seems to be getting worse, at first it was slight smell of fuel from behind, but now it is always pukeing out clouds of black smoke at idle, and under part throttle it gets worse and throttle response is mushy with even more black smoke,
when i first drove the car to the muffler shop with my n/a exhaust it was clean , crisp and powerful. with the turbos (no boost just free wheelin) it is insanely rich,
the efi is a cutler mpfi, a predesessor to the the holley commander. it tunes itself with very little exterior adjustments (acceleration enrichment, iac control, startup enrichment.)it runs of 4 sensors, map sensor, water temp, air temp and throttle sensor. could any of these be faulty and causing my problem??
the injectors are 38lbs which will be changed for 50lbs before i boost
if anyone has any ideas let me know... im listening or if anyone has knowledge of the cutler system???
also i have a small trace of oil in one turbo intake.. is this a sign of poor drainback??? the pressure line is 1/4" and the outlet is 3/8"
thanks for any input
jason

camcojb
07-15-2006, 06:30 AM
First off, you do not want to do a turbo setup with a processor that's not completely tuneable. There is no way I'd run that computer with that engine.

Yes, a bad or incorrect map sensor, bad or incorrectly adjust TPS, etc. will all cause problems. Will that ECU run a 2/3 bar map sensor? Which do you have in the car? You need at least a 2 bar map sensor to run up to 15 psi or so and I'm not sure that system supports one.

Bottom line, I seriously recommend changing your tuning system to something that can tune everything the engine will be doing. There is no way a self-tuning ECU will be the best way to go on a forced induction setup.

Jody

viper11
07-15-2006, 06:51 AM
hi camcojb
the sytem does have a 2 bar map and does support boost, but the boost is not hooked up yet
i do have a megasquirt but im not educated enough on that system yet to install it
i will be upgrading eventually but just want to get this thing drivin for now till i have the mega ready
jason

camcojb
07-15-2006, 07:14 AM
hi camcojb
the sytem does have a 2 bar map and does support boost, but the boost is not hooked up yet
i do have a megasquirt but im not educated enough on that system yet to install it
i will be upgrading eventually but just want to get this thing drivin for now till i have the mega ready
jason

So the turbos are on the car, but the outlets are not hooked up to anything? How do you tune the idle areas with that computer? What map pressure (KPA) reading are you seeing and is it steady? What TPS reading do you have at idle and how does the computer know it's idling? In other words, most the aftermarket efi's you set the tps to a certain % or voltage, and then in config you tell the computer that that voltage or % is idle, and above that is not. If this is incorrectly set then the engine could be off the idle fuel mapping.

At any rate, kinda tough to help as I have no idea what tuning that system allows. I have not seen mention of being able to tune the idle or cruise areas manually, sounds like it self-tunes those areas which limits your options to fix it.

Jody

viper11
07-15-2006, 08:38 AM
i know it seems weird ,there is no oxygen sensor or external hookup
heres a clip from the manual

9.0 USING THE ECM

The ecm is very simple and easy to operate. It can learn most functions needed to run an engine on its own, however there are several features and adjustments that need to be explained.

9.1-9.9 Priming, idle system, etc.

10.0 GENERAL TUNING INFORMATION

The ecm tunes by seeking out the peak torque an engine can produce at a given load. After every new point is tuned the ecm uses this new point as well as all the other previously tuned points to build a fuel map optimized for the engine.

The ecm is used on a variety of engine sizes and power ratings. Until the ecm has learned about your engine it may cause the engine to run rich. It may take several minutes to tun these first points correctly. As the ecm gathers more information about the engine and has built a more accurate fuel map, the final points the ecm tunes will take less time than the first points.

The ecm is tuning correctly when the Check Engine light is solidly on and the engine is either increasing in RPM or running at a constant RPM. Because the ecm has to wait for engine performance data to analyze and tune the engine, the lower the RPM the longer the ecm takes to tune. At 900 RPM the ecm can take up to 10 minutes to tune a point. At 3000 RPM, the ecm can tune a point in less than a minute.

When the ecm encounters an un-tuned point it will immediately start to tune. If during the first 8 hours of operation the vehicle stays at a load point for more than one minute the ecm will re-tune this point. After 8 hours the ecm will re-tune load points whenever the engine stays at a given load point for more than five minutes.

For the ecm to build an accurate fuel map it is very important that the ecm be allowed to tune every point it can. To optimize the tuning process, the engine needs to be kept under constant load until the ecm has finished tuning.

like i said it ran good at first but is getting worse
jason

camcojb
07-15-2006, 10:20 AM
Jason,

you're really wasting your time with that unit I think. No O2? How the hell does it know what it's tuning? Seriously, you cannot tune without know the a/f, and you need an O2 (wideband O2 to tune anything other than idle and light cruise) to know what the a/f is. What does it do, keep adjusting until it gets the best vacuum?

I guess you can try to keep running it and hope it improves, but I wouldn't even take a chance. If it's a new motor running rich is a great way to screw up the ring seal.

Jody