7mge fuel delvery problem.

[suprakidd]

hello supra mania im currently trying to get the 7mge i my 89' cressida running.

its got spark. but no fuel, i can hear the pump buzzing, so i know the pumps working.
but when i take off the "in" line for the fuel and crank it... nada.. :nono: so now im stuffed because toyota fuel filters are supposed to "not" need changing.

so could it be that the filters clogged?? or could the problem lye somewhere else?

 

[AJ'S 88NA]

Your pump maybe running but not have pressure or the filter on the pump itself maybe blocked http://www.cygnusx1.net/Supra/Library/TSRM/MK3/manual.aspx?S=FI&P=71

 

[suprakidd]

ok per that fsm i jumped terminals +B and Fp and the system didnt pressurize to the return line. i did take a peek into the cold start fuel line and the fuelrail is full of petrol...

so that leads me to beleive my regulator is clogged and my injectors arent firing because it should at least start with the fuel in the rail..

correct me if im wrong

 

[AJ'S 88NA]

Has to have pressure.

 

[suprakidd]

needs pressure to fire the injectors correct?

can the fpr get stuck open/closed and not allow fuel past?

im guna drop the fuel tank tomorrow a see what pump looks like..

any other suggestions?

 

[lewis15498]

Yes the FPR can get stuck. Wouldnt drop the tank just yet, its not going to tell you anything, just waste your time.
Get a fuel pressure tester, and test your fuel presure. Report back, and we can go from there.

 

[Poodles]

Pressure regulator is on the return line, not feed. Could be the fuel filter, but it's usually not.

 

[lewis15498]

If it stuck closed pressure would spike, but it may still start. If it was stuck open he wouldn't get sufficient pressure and it probably wouldnt start.

 

[suprakidd]

yea i dont think its stuck open because im not gettin any fuel past the fpr at all. but the fuel rail is full of fuel...

where would i put the fuel pressure tester? skrew it in where the regulator is??

 

[lewis15498]

Scroll back up to post number 2, click the link to the tsrm, AJ has already found the right page for you. Read that page, and the following page, it will tell you everything you need to know.

 

[suprakidd]

al right i connet it to the delivery line, torque it down then jump he terminals for the fuel pump.

i hope napa or auto zone has it, when im done il check in here and let you guys know.

if the fuel pressure is over 44psi then my fpr is bad.

if its below 38 psi it coluld be:

the filter (unlikly because im getin fuel to the rail)

hoses and connecton. (looks up to par to me)

the fuel pump (i can hear it but ill see if its making pressure tomorrow)

or lastly the fpr, il know if it is if the fuel pressure spikes, if not my moneys on the pump.

thanks again guys

 

[Poodles]

You check pressure at the rail throught he cold start line. Or, you could open it and jump the terminals to see if you get any to come out. Testing the main feed (that goes to the dampener at the back) and the return (which goes to the fuel pressure regulator at the front) is the hard way. Just loosen the bango fitting ont he bottom of the cold start injector and hold a rag to catch any spray and jump the terminals.

It's a dumb question, but is there fuel in the tank? What condition is the tank in? Rust in the tank will quickly clog the sock filter on the pump. The sock filter is why the fuel filter is generally not the issue, as it would usually eat the pump well before the fuel filter would clog. Unless it sat for a long time and clogged with rust (which is possible for all the lines).

 

[suprakidd]

i looked in the sending unit and its got gas in it. the condition of the gas or tank i cant really tell but il take i peek tomorrow with a flash light.

if it turns out to be the pump il get new sock, and try that out first, since if it is the pump il be replacing the sock anyway..

ima hit the sack il let you guys know what happens. THANKS!

 

[AJ'S 88NA]

You keep mentioning fuel in the rail, still has to have pressure.

 

[suprakidd]

correct i wont know for sure until i test it, with a fuel pressure gauge. which i plan on doing tonight after work.

 

[suprakidd]

i think i found the problem...

the sock has desinagrated.. :aigo:

is there a way i can see if the pump is good?

do i just summerge it in gas, give it 12V and see if gas comes out of the lines?

my thinking is if the pumps still good the it most likely didnt make to passed to pump...

any suggestions?

THANKS!

 

[suprakidd]

shes alive. i replaced the the pump filter, tested the pump and picked up a used fpr at mjz preformance (local supra specialist shop). and jumped the terminals. felt pressure in the return line. turn her over and WAHHHHHHHHHH!

lmao.
thanks guys.

hope this helps someone in the future