D16 turbo idle surge

[masonhenson]

Ok people. 1998 d16y7 greddy td04h turbo kit. Was on a 93 with a Scotty tuned p06. The car has 450 injectors with resistor box. When you cold start it it seems to hesitate starting and then when it does it idles at like 3k for a min or two then drops to 1400 and surges to 2500 over and over till it's warm, at that point it surges from 1100ish to 2100. It still has the y7 manifold. Intake that is. The greddy log style manifold only has one o2 sensor bung therefore we only screwed the precat o2 sensor in and plugged it in. We left the other plug just hanging. Could this be the cause? Any help will be repped to the fullest. Thanks
oh and I'm using an obd2a to obd1 harness and running the same p06 from the 93 d non vtec

[masonhenson]

no help?

[.:Stirfry:.]

i say clean out your IACV then go from there

[masonhenson]

will try. hopefully itll change something but it didnt do this right before i put the kit on

[.:Stirfry:.]

will try. hopefully itll change something but it didnt do this right before i put the kit on

thats weird
but the iacv controls the rpms through the temp..
did you unplug anywires when doin it?

[masonhenson]

just to to the injector reistor box.. can i test the wires going to the iacv? like for voltage and such? and also i replaced the pcv valve while doing it and may have cracked the hose.. would that cause this?

[oldcorolla]

Might have a vacuum leak from that hose if you did crack it , spray some wd40 on the complete length of the hose and if it idle out smooth for a second then goes back to the same thing you have found your issue. Do this with the rest of your vacuum lines also just to see.

[masonhenson]

i didnt realize the pcv pulled that much vacuum.. ill check whenever i get a chance to get under the car or inbetween the intake runner haha

[masonhenson]

Ok just noticed this. When the ac compressor turns on the idle levels out at 2k. Mean anything?

[seanrg1116]

if it has an atmospheric blow off valve that could cause some of your idle issues but not all, your problems sounds like a vacuum leak;

do you have a boost gauge?

How much vacuum is it producing at idle?
if its less than about 20 on the vac side than start looking for a loose or disconnected vacuum line.

[scttydb411]

if it has an atmospheric blow off valve that could cause some of your idle issues but not all, your problems sounds like a vacuum leak;

do you have a boost gauge?

How much vacuum is it producing at idle?
if its less than about 20 on the vac side than start looking for a loose or disconnected vacuum line.

atmospheric bov doesn't matter on a map based vehicle...only maf based vehicles. map based only sees what's after the tb/map sensor. any leaks after that will cause issues.

1. check the vac lines...any cracks in any of them, including pcv will cause idle surge.
2. any cel? the ecu was from another tuned car, but not this one and you have a y7. unless you did the 2 wire iacv conversion you will have a bad idle.
3. the tune is different and can be causing this as well, but i would check the aforementioned items first.

[masonhenson]

Did no 2 wire conversion. I have a 98 y7. The kit was tuned on a 93 y7 with a y8 manifold. Is that my problem? The iacv is the wrong one? No vacuum leaks at all. I will be changing to the y8 mani when I can get up the money to pay someone haha. I have a y8 mani and I believe I use my same tb

[scttydb411]

all 96-00 y7 use a 3 wire iacv located on the tb. obd1 ecu use a 2 wire iacv...the other car the ecu was tuned for already had the y8 intake manifold and 2 wire iacv. you need to get a 5 speed y8 intake manifold (auto y8 had 3 wire too) with the 2 wire iacv and the y8 tb without the 3 wire iacv. you'll need to do the 2 wire iacv conversion i attached.

[RBS]

any CEL's?

[masonhenson]

None