Car almost stalls when shifting ?

[Zrain25]

When Im shifting gears past 3000 rpms the engine drops to like 300rpms then back up to 800 when the clutch is in? Any ideas

I did have a issue with the tps my car wouldn't idle below 1400'rpms so I just adjusted it to get the idle down to 800 I didn't calibrate tps because i think it junk I need a new one idk if that would relate?

Thanks

 

[jake8790]

Mods?

 

[IndigoMKII]

When Im shifting gears past 3000 rpms the engine drops to like 300rpms then back up to 800 when the clutch is in? Any ideas

I did have a issue with the tps my car wouldn't idle below 1400'rpms so I just adjusted it to get the idle down to 800 I didn't calibrate tps because i think it junk I need a new one idk if that would relate?

Thanks

When you adjust the TPS you have to redo your CPS timing. Also, making the car idle down with the TPS isn't the smartest choice.. http://www.cygnusx1.net/Supra/Library/TSRM/MK3/manual.aspx?S=FI&P=101

Recalibrate your TPS correctly and reset your CPS timing and see if it improves.

 

[Zrain25]

ok im gunna tackle that this week end. what do i need to time the engine. i know i need a timeing light? anything else

 

[IndigoMKII]

ok im gunna tackle that this week end. what do i need to time the engine. i know i need a timeing light? anything else

Jump the te1/e1 connectors in the diag box under the hood.

 

[mkiiichip]

BOV vented to atmosphere?

 

[jonahs_supra]

was it idling at 1400 rpm when engine is cold or hot?
engine is suppose to idle at 1400rpm when cold and around 600 when hot

how did you adjust the idle?
you should look into your ISCV(idle speed control valve)

 

[Zrain25]

yes it came with greedy intercooler and bov. my cousin built 4 supras and he said the bov might cause that? and i ajusted the timing to 10 and the tps calibrated. starts cold at like 700 rpms then moves up to 900. ?

 

[suprarx7nut]

One more vote for blow off valve here. Very simple.

Metered air escapes, car thinks that air is going through engine, adds fuel, now its way too rich and it dies.

Sent from my Galaxy Nexus using Tapatalk 2

 

[Zrain25]

so what would i do to fix this, get a bov that opens and returns?

whats the best bov for these cars

 

[jetjock]

...starts cold at like 700 rpms then moves up to 900...

Might want to fix that first...

 

[Zrain25]

well i cleaned the iacv last weekend and now my idle isnt surging and its lower at about 900. it doesnt take long for it to get to 900 rpms. once it fires it idles at 700 rpms for 1 or 2 seconds then goes up steady to 900 and stays there.

im trying to get all the engine bugs worked out before i send it out to get painted so any info or advice is helpfull

thank you

 

[Poodles]

For starters, you don't adjust idle with the TPS, the TPS is set to a specific spec (and if it's out of spec still, it's replaced).

 

[Zrain25]

it wasnt out of spec i calibrated it the right way today with a meter. i also ajusted the timing to 10 before tdc.

 

[jonahs_supra]

I didn't calibrate tps because i think it junk I need a new one idk if that would relate?

Fix known issues 1st
Check for vaccum/boost leaks

once it fires it idles at 700 rpms for 1 or 2 seconds then goes up steady to 900 and stays there.

Should idle at 1400-1500 when doing a cold start then idle down as the engine warms up

 

[Zrain25]

I was going off my gut on the tps but when I calibrated it all the measurements were ok they were between spec so the tps is fine. I did a vacuum leak test it pulls 27hg at 900 rpms so I think there is no leaks. Boost leaks I haven't checked yet.

I did clean the iacv last weekend and it fixed the surging idle.

 

[mkiiichip]

I was going off my gut on the tps but when I calibrated it all the measurements were ok they were between spec so the tps is fine. I did a vacuum leak test it pulls 27hg at 900 rpms so I think there is no leaks. Boost leaks I haven't checked yet.

I did clean the iacv last weekend and it fixed the surging idle.

:nono:
Not that you need to be checking for vacuum leaks, but your not doing it right.

 

[Zrain25]

I sprayed carb cleaner on all hose too no idle change. I connected my vacuum gauge to a boost gauge T and it was pulling 27hg at 900 rpms I can't get the idle lower then That idk y. So I'm guessing if it pulling 27 at 900 it would probably pulling around 20hg at 700

What's the correct way?

 

[RazoE]

recirculate your BOV, adjust your TPS and check for any leaks.

My car would stall if I shifted into neutral even with a recirculated BOV for the past three years. Turns out previous owner had messed with the TPS big time, and the screw on the TB. Now I can let off full boost, and it'll return to idle at 650rpms.

 

[Zrain25]

I ordered a recirculating kit for my bov so it should be here end of next week