RckyMtnLegacy's 93 Turbo...On the Road Finally!

[RckyMtnLegacy]

Having all kinds of issues now. At quarter throttle the engine will cut out like a huge misfire and sometimes back fire really loud. Not the usual popping on decel but a bang like a gun shot. Hesitation is horrible

[Legacy777]

What has changed?

Do you know your AFR's when the popping/hesitation occurs? I'm going to assume it's pretty rich.

[mike-tracy]

Tokyo, nice! How long will you be there? I've seen the inside of Narita airport but never made it outside.

Just made another round trip through Narita, still haven't stepped foot on JDM soil

[RckyMtnLegacy]

That sucks! Trying to plan another trip out next year to buy a Land Cruiser to ship home.

[mike-tracy]

That sucks! Trying to plan another trip out next year to buy a Land Cruiser to ship home.

That would be amazing!

[RckyMtnLegacy]

I have finally gotten to get her back on the road after sending her off to have the wiring fixed by a friend during the pandemic. I am not having the shutter or cut out issue like before, found it was the ECU causing it to cut out. Pulls nice and hard to 4k and has much more but I am going to play nice for a while. Still feel like I will fail emissions but I will be trying again tomorrow.

[RckyMtnLegacy]

What has changed?

Do you know your AFR's when the popping/hesitation occurs? I'm going to assume it's pretty rich.

Hesitation and popping are gone. Just got the AFR and boost gauges installed.

AFRs are:
Idle-14.7
Cruising-14-15
On medium load 2000-4000 RPMs is drops to 13 stays steady.
Heavier pull it will go to 12 sometimes.
Then letting off the throttle and exhaust pops a bit it pegs past 20+ for a split second and goes back to 14.7.

[Legacy777]

Those AFR's are a little high. What boost are you running? I know the feedback I heard was to try and stay in the 11's.

[RckyMtnLegacy]

Boost is around 10-15 but have not pushed it

[RckyMtnLegacy]

I do get the CEL to flicker if I run it fairly hard to about 4k and get codes 24 and 45. Seems like pressure codes possibly boost too high? If I cruise slow through the gears light boost the flicker goes away. No fuel cut to 4k. I have not pushed it past that though.

[Legacy777]

Usually you address the lower code first, which would be the IAC valve....and that really doesn't make sense given the circumstances. Honestly, it still sounds like an electrical gremlin issue.

[RckyMtnLegacy]

Emissions has been passed! Looks like cleaning up the wires to the ecu fixed the super rich issue. Still get a CEL randomly but getting somewhere. Spent Wednesday cleaning her for 7 hours. Every inch sitting for 6 years was covered in all kinds of stuff. Still not finished but it's getting better.

[RckyMtnLegacy]

Finally back on the road! Failed emissions in 2021 and have been fighting it since. Finally passed emissions 3 years later and getting Hal-Tech installed Friday.

If you ever have super high HCs it might be where your O2 sensor is located. Mine was on down pipe getting almost 5x what emissions allows, moved to manifold and it dropped to a quarter what was allowed.

[Legacy777]

That's an interesting phenomenon.

So is the O2 sensor pre-turbo now or just after the turbo?

Was this causing it to fail in the closed loop mode running for emissions?

[RckyMtnLegacy]

The sensor was just behind the turbo. Now we have one further down the exhaust and on the manifold.

Was failing in all modes

[Legacy777]

Hmmm....that is the stock location for the O2 sensor. That is weird.

[RckyMtnLegacy]

Currently with Harvey (BoostCreep) with Haltech installed getting tuned.

Replaced Mishimoto fans as he recommended to upgrade as they apparently do not flow as well. Installing new Wide band as mine was not working properly.