Car is stock and still sputtering after maf change

[Turbo522]

I just bought this gsx eclipse and first of all the car was not even running on all four cylinders.
Ended up changing cam angle sensor and that caused both coils to fire(good to go). Then

I ended up having a check engine light with
12 Volume air flow sensor
13 Intake air temperature sensor
25 barometric pressure sensor

I replaced it with a spare Mass Air Flow sensor and 13&25 went away but still have the ecu giving me a code of 12. (how do i fix this problem?)

Now the car runs and when i try to open up; as soon as boost reaches 10+ it breaks up and sputters. only thing i can see is the car is running rich and black smoke from exhaust.

Should i try to find another MAF or should I take another route?

Thanks
D. Sanchez

 

[dsmloverguy90]

Could be a bad wire causing the problem with the maf. But for shits and giggles i would run a boost leak test.

 

[Turbo522]

Could be a bad wire causing the problem with the maf. But for shits and giggles i would run a boost leak test.

sounds like it can be the issue. The gentlemen I bought it from had a s-afc ; hks vein pressure control and msd ignition on it. may have accidently removed a wire. i;m going to check the wiring wed morning and get something built to perform boost leak.

will boost leak cause car to run rich tho?

Thanks

 

[woowoopdoo]

A boost leak will definitely cause the car to run rich. This is because the ecu puts the fuel needed for the air metered by the MAF. But when there is air loss(boost leak) it causes a rich mixture. Let us know how it goes.

 

[jc_is_the_man]

I had a similar problem...It ended up being bad wiring on the 2g maf, Whenever I would hit a bump it would cause the wire to loosen and spuuter at anythign over 2000 rpms.

But if you checked the wiring....here is a thread I was sugested to go through.
DSM Link Aquired (Running REALLY rich)

My original thread is here. GL with your fix
http://www.dsmtuners.com/forums/pro...ess-sensors-all-thrown-while-driving-ecu.html

 

[asexton6969]

As seen on Alldatapro.com

HARNESS INSPECTION

OPERATION

AFS is integrated in the air cleaner to measure the intake air flow rate by using the Karman vortex phenomenon. The Karman vortexes are asymmetrically and regularly generated downstream from the triangular pillar when the pillar is placed in the air stream. The generation rate of vortexes is proportional to the air flow rate.

AFS uses ultrasonic waves to convert the generation rate of vortexes into the pulse signal which is proportional to the air flow rate, and inputs the signal to ECU. ECU calculates and determines the standard injection time from the intake air flow rate signal and the engine revolution speed signal (crank angle sensor signal).

On the turbo vehicle, to eliminate the measurement error of the intake air flow rate influenced by the turbo system during deceleration from high speeds (high load) in the turbo supercharging state, another circuit is added to send the reset signal from ECU to AFSI. When the reset signal is inputted, AFS resets the modulator to select the circuit which attenuates the turbo noise.

TROUBLESHOOTING HINTS



If the output frequency of AFS rapidly varies greatly, it may result from an improper contact of the AFS connector.
If the AFS output frequency is excessively high or low, check the air cleaner element.
If the AFS output frequency is high, the engine resistance may increase or the compressed pressure may leak.
If a wire is broken in the filter reset circuit of a turbo vehicle. shock may be felt during deceleration from the high speed (high load) operation.

Hope that helps sir.

 

[Turbo522]

WOW! Thanks alot. great info everyone. Thanks to all. will perform checks in the AM tommorow morning. checking for vacuam leaks is gonna be a nightmare. i can see it now. :_)

 

[Turbo522]

with factory setup. where do you guys like to hookup the tester or how do you guys test for boost leaks? fill me in on some of your inventions or items bought.

 

[asexton6969]

Silicone coupler, plastic pipe cap. Drill a hole in the cap (not too big) just big enough to pull a valve stem in to it. Some people will drill a second hole to put another valve stem in to hook up a pressure gauge. Remove the intake pipe, install the boost leak tester on to the intake of the turbo. Pressurize the system, use soapy water and your ears to find leaks.

IC Pipe Tester

 

[Turbo522]

Thanks for all the help. I ended up checking voltage on the harness connector which connects to the MAF and didn't get the 5volts. Then I check continuity and nothing. after removing the ecu; found a wire cut and grounded it to see if it was the same one which is connected to the pin to the maf sensor and of course it was. after soldering it ; it was running a whole lot better ; but unfortunately it didn't rev like before and check engine light came right back on. It showed up as the ignition power transistor. I also have a 1992 in the garage which has a bad motor so I Cannabilized the part from it. After replacing "power transistor; the car worked as advertised and ran perfect. after putting everything back ; I started the car and the car had slow rev again. I checked ignition and lost number 2 and 3 spark. DAM! ; back to square one almost. the power transistor off my 1992 may have not been in the greatest shape either. i;m going to see if I can try a new one from the store. if that works, then fails I may have a bad ground/short.

Thanks again for the schematics and diagrams. they worked like a charm.

D. Sanchez

 

[Turbo522]

k; this is what i did after fixing wiring. i used the 1992 power transistor out of my other gsx and it worked fine untill i tried to start the car again after putting up the ecu and noticed slow acceleration due to loosing spark in number 2 and 3. I;m gonna try another power transistor but has anyone ever had this issue before? according to my manual i was supposed to apply 1.5 volts to certain pins on the transistors which i did and it checked fine. i checked resistance on the coils and they both came out almost equal. will be keeping you guys posted after i try another transistor; if it doesn't work then i;m back in square one. . wow. starting to feel like i;m chasing my own tale. previous owner had the wiring screwed up and who knows what else.

 

[Turbo522]

Ecu was cause. it would only send a signal to the one set of coils. thanks everyone for there help.

SWEET!

 

[4yoto24]

i having the same problems! my car will not start, its not getting a spark, and when it did start before i wouldnt be able to rev more than 2500 rpm, please help.

 

[4yoto24]

the car would sputter or missfire after 2500 rpm