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I have 87 conquest broke off spark plug, got new head no auxiliary valves, T3-T4 turbo kit, GM MAF sensor, cone air filter and MAF Translator gen1. Got it back together ran good but had turbo leak look like return pipe, took off and back on a few times still leaked called Top End Performance they said turbo was bench tested and couldn't be turbo leaking. After giving up for a while and trying again a few times over the years when I retired took off turbo and rebuilt it, had a broken o ring in it. Put back together no leak and detailed engine department ran alright till got warmed up and leaned way out, changed temperature sensor, checked TPS sensor ok, ISC motor bad changed and timed them, good fuel pressure dialed MAF box back and fourth many times still runs good on  wide band air and fuel gauge when cold but when warms up leans way out runs a little better with AC on for some reason. Long story  but thought might help, don't know what I did but need some help to get running right would really like some advice. THANKS BRIAN MCGUIRE   

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16 minutes ago, Brian McGuire said:

still runs good on  wide band air and fuel gauge when cold but when warms up leans way out

To be clear, are you using your wideband's narrowband output as your ECU's O2 sensor input? I've heard people having problems doing this.

Otherwise, it sounds to me like it's a vacuum leak somewhere. Kinda lines up with the A/C being on; more load on the engine=less vacuum to leak. I'd set the MAF-T to base and start spraying brake cleaner around the intake piping/vacuum lines while watching the wideband output to see if it spikes rich at any point. I had a similar issue that ended up being a 1G DSM recirc valve being set up like a blow-off valve; leaked vacuum when it got warm.

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2 minutes ago, Brian McGuire said:

I have AEM 30-4100 gauge type UEGO controller  bosch oxegen sensor LSU4.2  uego sensor


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