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No fuel to tbi after sitting for 2yrs..

998 views 6 replies 3 participants last post by  Plentychevy 
#1 ·
T.i.a....
ANY IDEAS..

I'm lookin atta 90 2d swb 4wd 97,00 originalmiles... it was parked by the owner 25 months ago with passenger rear brake issue..
Turns over.. will fire with a starter fluid... see no gas pumped at tbi..this...an hear Fuel pump come on and prime.. Thanks again in advance...
 
#2 ·
Are you getting spray from the injectors into the manifold?

Check the fuel pump. Remove the fuel filter under the drivers door and turn the ignition on. If it works you will have a puddle on the ground.

If there is no puddle then you need to see if you have clogged fuel lines, bad fuel pump, bad fuel pump relay, etc...

If you have a puddle then you need to make sure you have pressure at the TBI.

If you have pressure then you need to make sure you have signal going to the injectors. They work on a switched ground signal. When the ignition is on one wire will have constant 12+ the other is the one the ECM uses to fire them. You can also remove the injector clips and hook up a small 12V light bulb and crank the motor to see if it lights.

That is just a starting point, it gets more in depth if you don't find your issue doing the above.
 
#3 ·
Are you getting spray from the injectors into the manifold?

Check the fuel pump. Remove the fuel filter under the drivers door and turn the ignition on. If it works you will have a puddle on the ground.

If there is no puddle then you need to see if you have clogged fuel lines, bad fuel pump, bad fuel pump relay, etc...

If you have a puddle then you need to make sure you have pressure at the TBI.

If you have pressure then you need to make sure you have signal going to the injectors. They work on a switched ground signal. When the ignition is on one wire will have constant 12+ the other is the one the ECM uses to fire them. You can also remove the injector clips and hook up a small 12V light bulb and crank the motor to see if it lights.

That is just a starting point, it gets more in depth if you don't find your issue doing the above.
I very much appreciate your offering of help.. I will begin from beginning in the morning..
 
#5 ·
The biggest pain is that the TBI units do not have a Shraeder valve to check fuel pressure. The easiest way I have found is to put a T-fitting inline with the fuel filter or instead of the fuel filter.
 
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#6 ·
No spray at injectors is most likely ignition module inside distributor, pick-up coil is probably next to go out, in other words just put a whole new distributor in, it'll be cheaper in the long run
 
#7 ·
Unless pump isn't working or possibly rubber hose from pump motor to sending unit line has blown off, I've seen this happen more than once, if it sounds like a water fountain inside your gas tank then your hose probably blown off
 
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