Car stall when MAF plugged in? '98 V70

Post by **abscate** » 28 Jul 2017, 08:22

Look for a front air dam grill for me please - lost mine on the radiator job a few months ago.

Passenger side

Post by **erikv11** » 28 Jul 2017, 10:29

Unplug the stinking MAF!! lol. 3 pages still haven't ruled out the MAF

Post by **bmdubya1198** » 28 Jul 2017, 11:49

Look for a front air dam grill for me please - lost mine on the radiator job a few months ago.

Passenger side

I passed one up a couple months ago. I went back 2 days later and they were gone.
I need it more!!!

erikv11 wrote: 28 Jul 2017, 10:29 Unplug the stinking MAF!! lol. 3 pages still haven't ruled out the MAF

I'll do that today and run without it for the weekend!

Post by **bmdubya1198** » 28 Jul 2017, 14:44

Just took it for a drive with the MAF disconnected. The idle didn't go down, but when I got home it did go up a couple times to probably 1.1k-1.2k. It felt rough, but it wasn't pulsing like it was before.
So I plugged it back in and took it for another drive. Now the boost is spiking!
In first gear it went to like 6, which is a little high from what I read (from one person on Swedespeed who claimed to have heard from iPd that max boost in 1st is 4.5 psi, so don't know how reliable that info is). Once I got going, I opened it up a little bit and it spiked to 10 PSI, which is way too high to still be on the TCV. And yes, all the TCV lines are connected properly. I let off, then boost it up again and it's boosting normal (5.5-6 PSI). Next intersection I pull away from it boosted to around 4.5 PSI, as it's supposed to.
Maybe this was just the ECU trying to relearn after the MAF was undone, but I think there's a problem.
Also, once I got back the fuel trims were all over the place. Anywhere from -8% to 14%. I tested this at idle (~950 RPM), 1,500 RPM, and 2,500 RPM. The RPM was also pulsing as I held it at 1,500, going between 1,400 and 1,600.