car running lean

virgs93sc

Registered User
I just installed 38 lb injectors with a 76 mm maf with the 38lb sampling tube, my car would studder real bad under any load, took it to a shop and they said it was running dangerously lean, they put the old maf back in and it runs 99% better but I still have the 38 lb injectors, what else could it be and how is the car running ok with the stock maf and 38 lb injectors?
 
Are you still running the stock fuel pump?

It's possible your pump is not able to maintain the pressure needed for your 38# injectors.

Just a guess.
 
What kind of intake do you have? Did you leave out the oring in the C&L Maf? What color sample tube do you have?

Jeff
 
I have a 255 lph pump and the shop said that the sampling tube is orange, I'm pretty sure that the o-ring is in there.
thanks for your help
 
I was under the impression that if you change injector size.That
you need to reset the computor to tell it of the injector size.And on
C&L MAF you need the proper sample tube to match injector size.
Have you tryed a chip in the computor,burnt to match the injector
size.
 
You only need to have the proper sample tube. This fakes the EEC allowing you to run larger injectors.

Jeff
 
Well it's not the first time I have been wrong,just the impression I
got from reading other post here.

but common since tells me, to get a proper A/F ratio,and tune. You
would need to tune the SC on a dyno with 02 sensor and a chip burn.
 
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With the correct sampling tube on a C&L, you can run 36 and 38lb injectors even as far as 42lb injectors with out having to play with the EEC or burn a chip.

If you have a MAC cold air intake you want to rotate that C&L about 90 degress so the electronics sit sideways.
 
I like to get my sc as close to perfect as i can.And i still have problems pop up.
But if the general area of a tune is all right.I would half to agree with every one.
 
my intake

I have a zr motorsport intake, I had it before anything else, It has the filter in the bumper, what is the mac one like?
 
Try to rotate the MAF anyway. Some people have had problems (with the MAC) because of the bends b4 the MAF.

Jeff
 
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