KA-T issues(starting problems and idling problems)

[hunter8411]

Before I start let me say that I have searched up and down Zilvia, KA-T.org, and google in general for a resolution to this problem, however nothing has worked so far.

*****For Cliff Notes Skip to Bottom of Page, this is a LONG read********

I come to you guys as a last resort, and hopefully a fresh look at this issue.

A little background first about the engine. It is a rebuilt KA24DE, that has about 3-4k miles on it and was running perfect before I put the Turbo kit on.

The turbo kit is:

T3 .48/.60 Garret(from a volvo)
550 Deatchwerks injectors(just received them back from cleaning/flow testing)
Top mount manifold
Front Mount Intercooler
Recirculated BOV
Enthalpy Tuned ECU
Z32 MAF

Ok it all started with a stuck injector, so I sent out all the injectors to have the cleaned and flow tested. Received them back and car started and ran like a champ. Took the car out for a test drive and it was lacking power and would not go into boost correctly.

I checked all vacuum lines, all IC piping for leaks(made a boost leak tester), adjusted BOV, and adjusted Timing.

Car was running much better than before and boosting perfectly. However somehow my Powersteering pump had lost tension somewhere along this way to the point of no longer pumping(yes I know very bad). So I tightened it back down properly.

And this is where the problems come into play. The car will not start UNLESS I hold the gas pedal down all the way and crank on the car for 10-15seconds. And when the car does finally start it will not idle, it will just stumble and die unless I give it gas. The car runs perfect when driving, except if I rev it up and just let off the gas it will die on me.

Through all the searching this problem points to a bad CTS (not starting and dieing when rev'ed up), however I changed the CTS to a BRAND NEW one from the Nissan dealership and it has the same problem.

I've also tried a second MAF to no resolution.

Adjusting the idle screw does nothing, unplugging the TPS actually seems to raise the idle like 50rpm.

Also I have a Wideband installed and when the car does run, it runs at a constant 12.2ish give or take a few .x's.

Anyone have any suggestions?

************************************************** *****
CLIFF NOTES
************************************************** *****
Motor is Rebuilt
KA-T setup installed
car will not start unless pedal to the floor and crank for 10-15seconds
car will die if rev'd and let off the gas
New CTS installed, and no vacuum leaks(tested).
AFR is around 12.2

[ak_slick]

Is you iacv clean?

[UNITEDMASTER]

Hello I would also say have a look at the IACV, also double check the TPS RPM should jump a bit more than that when unpluged,& double check the physical timing(remove valve cover & rotate engine & see what ya got.!!! HOPE THIS HELPS!!!!

[hunter8411]

I double checked the timing a few times. Pulled the distributor and reset to TDC, then reinstalled to proper position. I do believe it maybe the IACV because I try to adjust the idle on the manifold with the screw but it makes NO difference what so ever on the idle of the car.

I didnt have any carb cleaner to try and clean it out today, so I will have to wait on it untill tomorrow. I just hope it isnt bad.

[hunter8411]

Update:

I ran a whole can of Carb cleaner through it and it did not help the issue. Adjusting the TPS does nothing, adjusting the idle screw does very little. Unplugging the CTS and TPS does nothing. I'm thinking the IACV may be bad or the wiring to it may be bad.

I'm going to have to wait untill next week when I can get my hands on a Snap-On consult to plug in and check everything the ECU is reading.

If anyone has any other suggestions please let me know.

[ak_slick]

I have a solution for you... get megasquirt. It is what I ended up doing... makes stuff much simpler. But it does cost a little bit of money and takes a little bit of time.

Otherwise did you unbolt the iacv block and clean it out being able to see if it was actually clean?

Another thing, when you rotate the distributor back and forth while starting does it make a difference? It sounds like you could be a tooth off on the distributor and possibly off on the physical timing. But that doesn't make any sense since it was running just fine.

It's a reach but it is an easy check that always relieves my mind. Have you done a compression test?

[hunter8411]

I double checked the timing like 10x, even pulled the distributor a few times and double checked. I'm almost 100% positive its good, however I haven't had a chance to pull the IACV off yet.

I am really leaning towards the IACV as possibly the problem. I just don't have time to pull the manifold apart right now.

It's just weird because the car runs fine with just a little bit of gas, or under any type of acceleration. The AFR's are a little rich but still fine, and there is plenty of power. It just happens to die upon high throttle and letting off the gas, wont idle on its own, and won't start after being warmed up without being given gas.(CTS gets proper voltage from ECU and the OHM's are correct off the CTS itself)

Megasquirt is out of the question, don't have that kind of money to spend.

[FaLKoN240]

Are you sure your MAF is grounded correctly?

I had problems similar to yours, I just forgot to reground my maf in all the confusion of taking the car apart.

[hunter8411]

I am pretty sure I ran the ground from the maf correctly. I will double check it first chance I get. Once I get a consult I can double check what is reading properly and it will be easier to troubleshoot.

Thanks for all the advice guys.

[importdude]

make sure its not running 3 cylnders or less

same thing happend to me

from leaky injector to bad maf