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Problem with SC

Hello guys
Today I finish instalation of Eatons supercharger MP62 to my Exp 98, 4.0 SOHS
Unfortunately, I has not good result. So, I need your advice
I will try to describe you symptoms of problems – please, if you know, advise me possible reason and what I should to do for resolve it.
So, I install everything, duble check it all, and then I install tune program for Octane 91 by SCT tuner well and after it try to start engine. Engine was start, but idle - in first time it was very not stable – some moment 3000 rpm, other moment 500 rpm. And engine work look like only 2 or 3 piston work only. When I try to push gas pedal – absolutely no result. After some time idle became around 500 rpm, but still very not stable. After work about one minute engine stopped work. I check again all parts under hood and try start again. Engine started, but in same style.
Then I installed another program by SCT tuner (for Octane 93) and start engine – same result. Gas pedal not work, idle around 500 rpm and not stable too much. May be worse than before a little.

All of it was look like ignition work not correct. With both program I feel that some moment of combusting went to intake (opposite side), not to headers and mufflers. Voice of engine work has slamming.
So, I stop engine and go back to factory program. I start engine, and it immediately go to 5000 rpm idle and work there very stable. I try to push gas pedal – it was work good and very sensitive. I stop it.

So, now I need your help. Let me know your opinion – what may be wrong there? And what I should to do? Please, send me your answer as soon as possible
 



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Check to make sure you reinstalled your spark plugs wires correctly.

Make sure your MAF sensors is plugged in. I have heard something about turning your MAF sensor like 90 degrees one way to help when going forced induction.(and is the MAF sensor installed the correct way and not backwards?)

What happens when you run the factory tune?

Hopefully someone will have some better ideas, but make sure EVERYTHING is plugged in or in the right spot.

Also, did you install larger injectors? I have heard that the MAF sensor needs to be calibrated to the injectors or you could have problems.
 






One of the common problems for new installs is vacuum leaks. This makes the idle shoot up until the computer adjusts down. In your case, down to low.

If the gas pedal is not working then check the voltage on the TP sensor when applying the gas pedal. Maybe it's not latched correctly.
 






Thank you for your answers
I will check everything again

When I load fectories tune - engine immediately after start go to about 5000 rpm and keep it idle all time. In this case engine work stable. Gas pedal work ferfect. Egnition also work. Everything well, just idle 5000 :) So, gas pedal not work only when I install tune program (was include in kit from Explorer express, but make by Bamachips) In this case in general engine work, look like only cuple pistons in action.

Larger ingection also was installed (was include in SC kit) And MAF also new one and it also was inklude in same kit
 






Maybe your tune is wrong? Since you say it runs fine on the factory tune but only at 5000rpm, maybe your throttle cable is too short? I'd unhook the throttle cable and start it up again. Make sure the Throttle body is closed and adjust the idle up until it reaches 750rpm or so. This is assuming the cable is too short and maybe the throttle body is adjusted wrong.
 






BINGO - throttle cable was too short. So, I resolved this mistake - engine work now much better.
Thank you very much guys. You really help me.
Now it is works well on parking. Idle is well. Gas pedal is work well. Everything are looking good. But only when car do not drive. In driving the motor has not power. Beginning of driving is very slow, and if I kick down gas pedal at maximum in beginning of moving – then car drives very-very slow several seconds (about 5). I tried to change tuning program and look at results. So, car did drive better on stock program than on tuning program for octane 91 (I use gasoline 91) But anyway, not so fast as before SC installation. Especially in start moment. My service men connected his computer and tried to check everything. He doesn’t know exactly, but he thinks that probably fuel pressure is not enough. And he thinks also that tuning program is incorrect probably.
So, could you let me know, which pressure should be in fuel line as minimal?
What do you think about it?

One more question – Now I leave stock program on my car, because it work better. How do you think – may I use it some time without making damage to engine?
Thanks all again :)
 






No, I wouldn't use the stock program for long. The fuel trims are too lean up top and they'll be too much timing. Maybe it'll run good for awhile but it's dangerous.

Doug at Bama chips made that tune by testing many 4.0 supercharger applications so I'm willing to bet it's right. Something else is the problem but I'd make sure you've got the right tune.

If you floor it and no power then I'd say you're lean on fuel. You really need a wideband air/fuel gauge so you can see.

I can't remember the exact pressure? 60 - 80 lbs? I'm sure it's on the site somewhere if you'd like to look it up.

Make sure you have a good fuel filter. (New)

Anyways, look at the fuel side first.
 






It does seem as though you have a fuel problem and Jakee would be the guy to understand this better because I know he's been through the trails and errors of a boosted engine.

Another idea is maybe the spark plugs? If they are old and worn, the added boost may cause spark blowout?
 






Yes, you're right. The sound will be distinct with spark blowout. pufff pufff pufff cut out cut out cut out. But now that I think about it, you're on to something with the spark plugs or wires. Check all the connections to make sure they're seated correctly. Just one being wrong can cause this issue.
 






I'd say we are both coming up with some great ideas!!! Just hope rabellll figures it out so that he can enjoy his ride.
 






Thank you guys
I will check wires of ignition again. In this year I installed all new - JBA spark plug wires and Accell ignition coils. Everything new and perfect, but I will check connections.
I already have air/fuel gage, but monitor was brocken - so, I wait changes of it by warranty. So, I will look at this after a weeks or more.
Fuel filter also was almost new, but now I have desission to upgrade all fuel system include filter of course.
Anyway, after week I will go from Russia to USA for about three week - to SEMA show first, and for a week to Miami for holidays. So, I will return to my truck just after month :)
 






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