As the title says....
I will give a little background on the motor below. I am pretty sure I covered everything. I don't post often, but get a lot of info from everyone's posts on here. My problem is (and yes I have looked everywhere and tried almost everything, I believe for an answer) on deceleration, my AFR's drop to about 9 or 10 for a brief moment and then the computer looks like it is trying to compensate and leans it out for a moment to correct. This causes the exhaust to smoke (decent amount sometimes) and sometimes die when coming to a stop. This will happen at lower RPM's as well as higher ones. Any insight someone could give or help out with would be much appreciated.
I have tried finding a mechanic that will look at it and no one will work on the car since its been modified quite a bit. The car has been sitting in my garage for the last few years and every summer I get it out to try and fix and get frustrated enough to put it away again.
I had an SAFCII on for a while, but didn't know how to tune it, so I removed to try and eliminate a variable. I have read in a few places that it isn't necessarily required with my mods? Also, I don't think the SAFCII can adjust the fuel curve on that low of throttle.
I have gone through and did an intercooler piping pressure test. Found a couple small leaks at clamps and fixed. Otherwise this seems good. I pressurize up to 15 psi and the pressure seems to take about ten-fifteen seconds to drop to 5 psi and then really slowly after that. test was done with gauge and air pressure hooked up to turbo inlet and capped off at the end of the 3000 pipe.
My vacuum holds a steady -18psi at idle and every vacuum line seems to be hooked up and running fine.
Has newer copper spark plugs.
Timing is set at 10 with the terminals jumped.
Replaced my iascv (with another used one) recently, but seems to work fine, it clicks when the car is shut off.
checked my TPS per TSRM and it seems to check out.
Have swapped the AFM sensor with another before. I guess I could try getting a new one to see?
So I have no codes. My question is, what else could it be? Can a stock o2 sensor cause this or is 35 psi to high on the fuel pressure? The car seems to run great cruising and at higher RPMS, It is smooth power (no hesitations), and I have had it up to 17 psi so far on boost and has lots of power. Haven't been around anyone else's Supra before, but I do think my valves seem a little noisy (on the other hand I do know older Toyota valves can be a little noisy). The mechanic I did have take a look said the sounded normal though.
- 88 7mgte
- fresh rebuild with MHG (less than 1000 miles ago)
- wiseco pistons
- ARP studs
- BOSS TO4E 61 turbo ceramic coated
- 3.5" turbo back exhaust (no cat)
- 255 fuel pump
- RC 550's
- AFPR (set at 35 w/o vacuum)
- J tube bypass
- Larger aftermarket aluminum radiator
- flex-a-lite dual fans
- Cooleeze ceramic coated intercooler piping (including between AFM and turbo)
- cone filter
- BCC
- LEX AFM housing
- Greddy RS BOV (recirculated)
- Wideband o2
- Aluminum flywheel
- 6 puck sprung hub clutch
- Cartech intercooler
- deleted vacuum canister
- AEM Boost controller
I will give a little background on the motor below. I am pretty sure I covered everything. I don't post often, but get a lot of info from everyone's posts on here. My problem is (and yes I have looked everywhere and tried almost everything, I believe for an answer) on deceleration, my AFR's drop to about 9 or 10 for a brief moment and then the computer looks like it is trying to compensate and leans it out for a moment to correct. This causes the exhaust to smoke (decent amount sometimes) and sometimes die when coming to a stop. This will happen at lower RPM's as well as higher ones. Any insight someone could give or help out with would be much appreciated.
I have tried finding a mechanic that will look at it and no one will work on the car since its been modified quite a bit. The car has been sitting in my garage for the last few years and every summer I get it out to try and fix and get frustrated enough to put it away again.
I had an SAFCII on for a while, but didn't know how to tune it, so I removed to try and eliminate a variable. I have read in a few places that it isn't necessarily required with my mods? Also, I don't think the SAFCII can adjust the fuel curve on that low of throttle.
I have gone through and did an intercooler piping pressure test. Found a couple small leaks at clamps and fixed. Otherwise this seems good. I pressurize up to 15 psi and the pressure seems to take about ten-fifteen seconds to drop to 5 psi and then really slowly after that. test was done with gauge and air pressure hooked up to turbo inlet and capped off at the end of the 3000 pipe.
My vacuum holds a steady -18psi at idle and every vacuum line seems to be hooked up and running fine.
Has newer copper spark plugs.
Timing is set at 10 with the terminals jumped.
Replaced my iascv (with another used one) recently, but seems to work fine, it clicks when the car is shut off.
checked my TPS per TSRM and it seems to check out.
Have swapped the AFM sensor with another before. I guess I could try getting a new one to see?
So I have no codes. My question is, what else could it be? Can a stock o2 sensor cause this or is 35 psi to high on the fuel pressure? The car seems to run great cruising and at higher RPMS, It is smooth power (no hesitations), and I have had it up to 17 psi so far on boost and has lots of power. Haven't been around anyone else's Supra before, but I do think my valves seem a little noisy (on the other hand I do know older Toyota valves can be a little noisy). The mechanic I did have take a look said the sounded normal though.
- 88 7mgte
- fresh rebuild with MHG (less than 1000 miles ago)
- wiseco pistons
- ARP studs
- BOSS TO4E 61 turbo ceramic coated
- 3.5" turbo back exhaust (no cat)
- 255 fuel pump
- RC 550's
- AFPR (set at 35 w/o vacuum)
- J tube bypass
- Larger aftermarket aluminum radiator
- flex-a-lite dual fans
- Cooleeze ceramic coated intercooler piping (including between AFM and turbo)
- cone filter
- BCC
- LEX AFM housing
- Greddy RS BOV (recirculated)
- Wideband o2
- Aluminum flywheel
- 6 puck sprung hub clutch
- Cartech intercooler
- deleted vacuum canister
- AEM Boost controller
