Anyone ever burn out a stock ecu on a 89-92 7mgte? Symptoms? Thanks!

[7mgangsta]

So its lean at WOT as well?

Boost leak will cause a rich condition as metered air is not making it into the engine..

---------- Post added at 09:59 PM ---------- Previous post was at 09:58 PM ----------

Whats your fuel pressure at WOT?

I know boost leak would be rich but nice to know that everything is sealed up I guess, narrow things down. I have the fuel pressure set at 43 right now. precision turbo and engine told me to run their 550's at that. What is an average or stable afr under boost or wot?

 

[Devin LeBlanc]

Technically you shouldn't tune for a mentioned AFR.. Some tuners tune for best rich torque, some for best lean torque. It all depends.. But 11.5-11.8 Under 100% Wide Open Throttle.

You should zero the SAFC out or unhook it. Check you AFR's they should be pig rich.. in the 10's under WOT and 13-14's at idle and cruising. What turbo, boost, intercooler, piping are you running?

 

[7mgangsta]

Technically you shouldn't tune for a mentioned AFR.. Some tuners tune for best rich torque, some for best lean torque. It all depends.. But 11.5-11.8 Under 100% Wide Open Throttle.

You should zero the SAFC out or unhook it. Check you AFR's they should be pig rich.. in the 10's under WOT and 13-14's at idle and cruising. What turbo, boost, intercooler, piping are you running?

I wish it was that easy, I've tried that many times. I'm running lexus airflow meter housing with stock sensor (bad sensor?), 550's, fuelab afpr, fuel damper bypass, wal 255 with hotwire, 3" intercooler with 3" al hardpipe, ct26 turbo that I just put in so I know is solid, just did intake man gaskets, has metal hg with head studs and nothing much more that would concern afr's...

 

[Devin LeBlanc]

Something else is wrong..

 

[Poodles]

I agree, he's running higher fuel pressures so he should be crazy rich...

 

[Nick M]

Or the 12.5 number is wrong...

 

[Poodles]

Maybe he's misfiring?

 

[IJ.]

A miss will read lean on the wb02

 

[Poodles]

That's what I was thinking. As it all happened after a high speed run, could have fouled the plugs.

 

[7mgangsta]

Funny you mention that. I rewired the coil packs and put new plugs in it today in a desperate attempt to get it going before I bring it in to a local tuner shop and it was running a little better, I turned the safc down a ton and it ran even better. Still at 12.5 at 5lbs boost and still at 43 lbs fuel pressure. It won't go over 5 lbs boost without spuddering to all hell, so I'm now back to thinking it's a boost leak plus I had safc spiked and fouled plugs. I made a boost leak tester the other day and it leaks very slowly... Is a slow leak okay(like 1lbs a second) or does it absolutely have to hold pressure consistently? I'm also thinking about a new 02 sensor because it's still at 12.5 afr.

 

[IJ.]

When 02 sensors fail they usually default to 14.7

 

[Devin LeBlanc]

Yep, I recently had a WB sensor fail, it would read fine part throttle and driving around, but wot it would peg full lean..

 

[Nick M]

A miss will read lean on the wb02

Are there any widebands that can read CO2? Not to be confused with a 4 gas analyzer.

 

[IJ.]

Are there any widebands that can read CO2? Not to be confused with a 4 gas analyzer.

Never heard of one that can Nick, can't say I've ever looked or been asked this before.

 

[Nick M]

As you know, it would tell a lot more.

 

[7mgangsta]

So with all the things I have done to the car in the past month, everything has changed. Yesterday when I took the car out I turned the safc down on the High throttle map and it runs tits. So I guessing there were many contributing factors, but the safc and plugs took the cake. I tried turning the safc down before, but with bad plugs, it still acted up. Thanks for all the help guys, it's much appreciated. Now I just need a dyno tune, at least for the time being...