Sr20det won't idle-run/bogs. OK during Wot.

[illaim067]

I know "use search" I tried. Maybe I suck at searching. But anyways...

s13 sr20det only upgrades are fmic and straight pipe. Drove fine but it started to develop issue and has only gotten worse.

Cold/hot starts fine but will only idle for 1 min before it stumbles bad before dieing. Once it dies it still starts up fine.

Once driving if I drive normal it drives decent if I progress throttle. then once I keep my foot at the same position leaving the rpm in the same place (mostly low-mid rpm) it will start cutting and bogging bad but the second I give it full throttle it boost fine and climbs rpm no matter the rpm.

It basically needs the throttle pressed at all times.

I have new plugs (gapped .28) cleaned the maf. did the whole cleaning system with the liquid in the gas tank (throttle body cleansing) no leaks Any where. I don't know what else to do.

[jr_ss]

Do you have any vacuum leaks? Have you unplugged the MAF to rule it out altogether?

I'm leaning towards a big vac/boost leak and/or dead MAF.

[RalliartRsX]

.............No wideband A/F ratio gauge huh??

[illaim067]

Do you have any vacuum leaks? Have you unplugged the MAF to rule it out altogether?

I'm leaning towards a big vac/boost leak and/or dead MAF.

I havent found any leaks and ive given it a thorough check also. I haven't but I will Try that out in a few. I don't know why I didn't think of that.

.............No wideband A/F ratio gauge huh??

no....:bite:..stock sr ecu.

[jr_ss]

If it idles with the MAF unplugged, start searching for a replacement.

[RalliartRsX]

Tough to diagnose without most of the pertinent information stream :(

As mentioned by jr, could be a very bad vacuum leak or a boost leak (two different entities) and both could cause similar drivability issues (one however will manifest itself in a higher than normal idle and the other will manifest in either sluggish boost response, low overall boost or just simply stumbling once it goes from vacuum to boost or all three).

Natural offenders

1) TPS (when it fails, any depresion of the accelerator initiates an immediate stumble and potential shutoff.........similar to a major boost/air leak post MAF)
2) Bad MAF (does not rev above ~3K RPM and major stumbles above a certain percentage of throttle input. If nothing changes when unplugged, thats also another sign of a failing MAF)
3) Vacuum/boost leaks (as mentioned above)

[ultimateirving]

Tps is a valid answer. But a boost leak will not be possible if it pulls fine Wot.
(Ps, if you have never done a boost leak test then you need to because turbo)
Maf could be faulty especially the wiring and connections if you didn't do right them yourself or pay someone to do them.

Lastly I would consider the iacv for your idle issues as they are very susceptible to issues and a quick removal and cleaning can really help.

[steve shadows]

Actually you can have a boost leak if it's minor and only have issues in Low RPMs and then under heavy load it will seem normal but your AFRs and fuel delivery logs will be all screwy.