A few months back I purchased a 89 supra (7mgte) for $300. The car is currently not running. It has about 2-3 lbs of pressure. I thought for sure it would be the pump and I put one in it and new filter and its still doing the same thing. The car will start if u feather the gas when u crank it. It tries to idle @ 700-800 rpm. If u hit the gas it will back fire once in a while and it stalls out. U can hear the turbo charge up and blow off. I checked the voltage to the pump and its good. Someone told me it might be the ECU, but Im not for sure. Has anyone had this similar problem? Am I stuck with a bad MK3? Someone please help.:1zhelp:
Help needed. Fuel pressure
- Thread starter bigboostinmk3
- Start date
bigboostinmk3 said:
From your post I am assuming you are a fairly competent mechanic... so with that said. If you are only getting 2-3 lbs of pressure, my first step in diag would be as you stated the pump. Also check for a restriction in the pressure line to the rail, also have you checked the FPR??? they are a diaphram style regulator and can burst, causing fuel to come out of the vacuum port on the regulator. Pull the vacuum hose off check for fuel coming out of there. If ther is no fuel coming out. Pinch off the return line, then check your pressure, could be that the regulator is hanging open. if nothing there, hook a volt meter to the Fuel pump pos / neg have someone try to get the turbo to build pressure, watch the voltage as it hits boost. If i remember right, it should raise the voltage a little bit. If not check your boost pressure sensor or posibly the ECu as you said. hope that all helps. And for the hell of it verify the ground for the pump. turn your DVOM to the Mv scale black lead to neg. batt post, red lead to the fuel pump ground. anything more that say 50mv should be cleaned and or repaired. have fun good luck..
Sounds like multiple problems.
First, try and pull codes.
Then, replace the fuel pressure regulator and inspect the fuel pump.
First, try and pull codes.
Then, replace the fuel pressure regulator and inspect the fuel pump.
backfire has to do with ignition issues most of the times.
pull codes,
check timing
check spark on every plug.
check every sparkplug
pull codes,
check timing
check spark on every plug.
check every sparkplug
jetjock said:
well he does, least he checked fuel pressure..... better then some "tech's" i've worked with. :nono:
also with your turbo spooling... does it do it at a low engine speed... a misfire on some cylinders will cause the turbo to spool a little faster i'de listen to the other guys as well. sort out your pressure problem then diag the ignition system. keep updated i'm interested to see the outcome..
My money is on the fuel pulsation dampner being clogged or the fuel pressure regulator being blown.
Check your fuel pressure at the fuel rail input near the back of the motor and at the point of the FPR on the front of the rail.
I think that you may have some blockage in your FPD. I think the same part is on the turbo 22r and some other engines. You can do a part number x-reference search on toyotapartscheap.com to see what else you can pull it off of
Check your fuel pressure at the fuel rail input near the back of the motor and at the point of the FPR on the front of the rail.
I think that you may have some blockage in your FPD. I think the same part is on the turbo 22r and some other engines. You can do a part number x-reference search on toyotapartscheap.com to see what else you can pull it off of
Thanks for all the posts guyz and advice. Ive purchased an adustable regulator on the net. Just for later purposes. If that doesnt fix it.I will pull the F.rail and injectors and inspect.I noticed that some of the bolts on the upper plentunm were loose. My dad seems to think its a bad injector. Ive checked the whole ignition system everythings good firing oreders fine. Meanwhile I know this guy that is parting an mk3 out and has an ECU from an 88 7mgte. Its only $50 plus it might come in handy later on. I will post updates soon. I cant wait! Thanks again for all input I will try everything to REALEASE THE BEAST
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Betting on the Fuel pressure damper or the fuel pressure regulator. Check pressure at the fuel rail before removing from car. Also check the regulator vac hose for fuel. I know this was previously brought up by other people. JUST MAKING SURE YOU DO IT