Got everything up and going, I took it for a test drive and when you accelerate it bucks and surges. The car idles just fine but when you try and go well it's a sad sight. Maf or chip problem?
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Got everything up and going, I took it for a test drive and when you accelerate it bucks and surges. The car idles just fine but when you try and go well it's a sad sight. Maf or chip problem?
Sounds like a MAF situation to me ! Whats your combo ? Injector size, etc, etc...
Pro M 80MM, 30lb injectors the pro m is configured for that setup. 255lph walbro fuel pump, and chip that came with the procharger, do I need just rotate the maf around till it runs right?
Sometimes rotating the MAF helps alot. Especialy if its located after a bend in the intake track. What about a FMU ? I heard the chips Are always set way to rich, never used one just heard alot of people complain about them.. Is this on a camaro or what ?Quote:
Originally posted by Zulater
Pro M 80MM, 30lb injectors the pro m is configured for that setup. 255lph walbro fuel pump, and chip that came with the procharger, do I need just rotate the maf around till it runs right?
96 Cobra, yes I'm running the FMU. Do I want to rotate the Maf while it's idling to see how she goes?
You do want to clock your MAF so that your sample tube is on the outside of the bend before it. Also, it sounds to me like plugs... what kind of plugs are you running, and at what gap? I'm supprised no one else has mentioned that.
I have done numerous blower installs (particularly ATI) and I have also seen many other peoples result when they install them and if you don't have the right plug and it's not gapped right with a blown application, it is going to do miss, spit, and sputter under acceleration (idle just fine)... and the harder you accellerate, the worse it get's.
I have NGK tr6 plugs set at .35 gap.
I don't know the heat range of those plugs... but if they are stock replacements (and stock heat range), you might want to go one or two steps colder... if they are only one step colder, go one more. Your gap is too large either way and thats more than likely your problem, anybody will tell you that... especailly if you are running off of the stock ignition system. Gap those plugs down between 25 and 28 and it should get rid of that for you... it sounds like a small gap, but that is what everyone that has good success is doing and it seems to clear up just about all of their misfire problems, especially up high in the RPM's. Do that and then post back with how it went, I can almost gauarantee that is your problem right there.
The plugs are one step colder, do you suggest dropping to .25 or somewhere between .25 and .28? The car idles fine but once you give it gas it chokes, I'll certainly give the plugs a try though sounds like an easier fix.
Yes, gap them down... start at 28 and see what happens... I bet you will be supprised. If that doesn't work, you can try a bit smaller, no smaller than 25, but if that doesn't work, try one step colder with the gaps mentioned here.
Will do thanks for the help, I'll post my results this evening.
Not a problem, I will be checking back later to see how it went. Good luck.:)
I regapped the plugs and it's doing the same exact thing, which direction is it going to be most ideal to rotate the MAF? Do I want the sensor on the Passenger side, driver side, front or back or just play until I get the desired result?
The car will not go up over 2800 rpm it's very very rough to that point but refuses to rev above that, should I pull the ecu and make sure the chip is still in solid?
Is the meter cal'd for 30's? If so, did you or your dealer inform Procharger of that. If not, the system (if its a stage 2) should have the calibration for the 30's in the chip.
Chris
I'm pretty sure the meter is calibrated for the 30's and it's a stage 2 as well.
I would call procharger and make sure that the chip is NOT calibrated for the 30's since your meter is doing the calibrating. If the chip is cal'd then the car would run very lean and likely pop and carry on like you described.
Chris
This may be a stupid question but could you have possibly crossed a couple of plug wires? It just seems really odd that you can't rev past 2800 RPM's. I don't know about you but I don't see any boost until 3000 RPM's so I don't think you're experiencing spark blow out or anything like that. Also, could you have possibly hooked up the FMU backwards? Believe me I'm no expert but I remember reading somewhere about an FMU being hooked up backwards caused a loss of Fuel Pressure. Just my input, good luck.
Justin
I rotated the MAF and bam she runs like a champ! Thanks a ton for the help.
Just like I said before... this is how you want to position your MAF. I am not sure if this is going to solve your problem completely though, sounds like some sort of callibration is bad. Have you pulled your chip out to see how the car runs like that? I wouldn't suggest running the car in boost, but you could see how it runs at least.Quote:
Originally posted by WA2FAST
You do want to clock your MAF so that your sample tube is on the outside of the bend before it.
This is a common problem when going to a blow through setup where there is a bend both before and after the air meter. We put the first blowthrough meter into Michael Plummers car years ago and it has functioned flawlessly but there is a pretty decent straight run before the meter. In the 96 and up cars where the meter goes inside the fender instead of in the engine compartment there is really no way to put the meter where there is a straight run of tubing. Because the air travels on the outside of the tube at low airflow, the sample tube must be on the outside of the bend. The problem with this is that it will tend to run rich at the top of the curve. If the chip is not custom tuned for the car, then you may not have an optimal a/f ratio throughout the whole curve. One option is to get a Pro-M Univer which draws it's air sample from 360deg around the meter. They tend to be quite a bit more accurate. Even then, I suggest finding a dyno with an A/F meter and make a pull.... check to make sure it is safe. Once you do get it tuned however, just a small rotation of the ait meter will affect the tuneup. Take care to make sure it always goes back in the exact same way it comes out.
Michael Freedman
Yeah, saturday she's going on the wideband to make sure I'm going to be safe. I bumped the FMU on the rich side just to make sure though, I can run riche all day long, but lean just a few times. The Pro M universal was going to be a winter project, I just purchased a home so mod money is tight, doh!