SR20DET Z32 MAF swap issue HELP!

[CurtisCh]

i've got an S13 with an SR20DET in it.
just picked up a GT2871R turbo, 740cc injectors, Enthalpy tune ECU, z32 maf
I bought the whole set up from a guy in the states that was running it on his s13 as well.
Put everything in the car and went to fire it up and the car runs rough at idle (5-600rpm surging) with MAF harness plugged in.
When you unplug the MAF, the idle goes up to 1200 and holds smooth there. Seems to run better unplugged.
I've checked on the ECU and it's not throwing a code for the MAF either... I've double checked my wiring for the MAF harness and from what i've read online, it looks to be sound. only thing i did was take the 2 black ground wires in the center of the z32 harness and tie them together into the single black ground wire on the s13 harness.

If anyone has any ideas of what to try next, or ever ran into this problem, help me out please! thanks much

[codyace]

Find a guide on a S13 SR to Z32 MAF plug swap and then make sure your timing is set properly, your TPS is set properly, and you IACV is set properly.

[CurtisCh]

Originally Posted by codyace

Find a guide on a S13 SR to Z32 MAF plug swap and then make sure your timing is set properly, your TPS is set properly, and you IACV is set properly.

I've used the guide to check the wiring on the z32 maf. I've tried switching the 12v and 0.5v wires too. The car ran fine with the stock turbo on it before i swapped all this stuff. does the timing or IACV need to be adjusted after a swap?

[ultimateirving]

Originally Posted by CurtisCh

I've used the guide to check the wiring on the z32 maf. I've tried switching the 12v and 0.5v wires too. The car ran fine with the stock turbo on it before i swapped all this stuff. does the timing or IACV need to be adjusted after a swap?

Yes I would check timing. And take one of the center grounds and put it to chassis to be safe. Lastly the iacv could have a different idle set point so it might need resetting.

Also ask if the tune has any advanced timing. I've read threads where peoe have reported needing to advance to 20*

[Mikester]

Hopefully you already put an upgraded fuel pump in to compensate for the higher fuel demand.

Second, what you are describing makes me wonder if the previous owner truly ever had that stuff installed & tuned. I'd check with Enthalpy- did PO provide any receipts with the purchase?

[CurtisCh]

Originally Posted by Mikester

Hopefully you already put an upgraded fuel pump in to compensate for the higher fuel demand.

Second, what you are describing makes me wonder if the previous owner truly ever had that stuff installed & tuned. I'd check with Enthalpy- did PO provide any receipts with the purchase?

Yes upgraded fuel pump and FPR. PO sent me a video of the car running with the parts on it. He just told me i have to advance the timing 20* to work with the enthalpy tune. no receipts.
Ive grounded the 1 ground wire to the chassis as well.
ill try advancing the timing now.

[Mikester]

^^Be careful. Hopefully you have a wideband. If not, you may want to invest in one before beating on it.

[codyace]

Originally Posted by CurtisCh

Yes upgraded fuel pump and FPR. PO sent me a video of the car running with the parts on it. He just told me i have to advance the timing 20* to work with the enthalpy tune. no receipts.
Ive grounded the 1 ground wire to the chassis as well.
ill try advancing the timing now.

*DO NOT* put timing to 20 unless you are 100% sure you need to. No reason to potentially melt a piston if you don't need to.

[CurtisCh]

ended up putting the car back to stock so i could make it to an event that night. I'm in contact with Martin from Enthalpy now, so when i try to install again, i'll get him to help me along. thanks all

[JesterX18]

I'm having the same issue except mine also stalls most time with MAf plugged in.. Did you ever resolve your issue? Same set up with z32 except mine is a jwt tune...ur problem sounds like the wires you crossed...

[CurtisCh]

Originally Posted by JesterX18

I'm having the same issue except mine also stalls most time with MAf plugged in.. Did you ever resolve your issue? Same set up with z32 except mine is a jwt tune...ur problem sounds like the wires you crossed...

My problem ended up being that when we did the swap we also installed a new fuel pump and fpr. We had the fpr wired up backwards and weren't getting proper fuel pressure to injectors. We had it upstream of the injectors instead of downstream. Switched the stock turbo back on and went to start and had the same problem as before, then realized the fpr problem. Fixed that, reinstalled turbo and car fired right up. Face palm.

Hope that helps

[xeros14]

I know this is an old thread but I am having a similar issue. I bought a new Z32 maf because i though my old one died it worked fine then one day my car went super rich 10:1 AFR i unplugged the maf while playing with the throttle so the car doesn't die then plugged the maf back in and the idle smoothed out and back to 14:7 AFR and ideas????? this has been happening lately and not sure why PLEASE HELP!!!!