Replace them both, unless the "sock" has collapsed inside the tank or you have another flo restriction somewhere you really shouldn't see that much pressure variation key on engine off, under idle or WOT. I am working on a 1991 Chevrolet S10 2. Video Title: Too Much Fuel, Fuel Injector Problems- Solving Idle Problems – EricTheCarGuy Video Description: In this topic, Too Much Fuel, Fuel Injector Problems, we look at possible fuel injector issues with your engine. This video demonstrates this process. I had a spare complete throttle body from a 90 burb, i put it on, same thing. I think the truck might have ground problems. The heavy deposits from poor fuel grades and lack of maintenance are considered an injector failure, which will require replacement. The most expensive option on Rock Auto is the ACDelco @ $59, i'd get that one or the Delphi. Rough idling – You may feel like the engine is going to stall when you stop. Tbi spraying too much fuel in engine. I have an old OTC monitor 2000 hand held diagnostic tool that allows me to scan thru various "modes" and look at IAC, TPS, BLM, O2 volts etc, as well as LED flags that indicate closed loop, open loop, TCC etc. Isn't this part of the signal for the injector to spray and being constant on would make injector stay on???.
Truck drives fine other than the bogging/bucking occasionaly and does not give a code. The Ultra Cleen Fuel System Cleaner Kit has been re-engineered to meet the needs of today's technician with a redesigned... Dual Purpose Set Detects Both Mechanical and Air Induced Sounds Use the black diaphragm chamber and screw-in metal probe to... The injector should NOT leak any fuel with it's connector off. An electric balance test for an electronic failure may be possible with the use of a scan tool. I don't believe you said anything about the service engine light( if it's a stock '89, should be lit up.. check the trouble before you try to change any sensors. Unplug the battery when unplugging the ECM Unplug both connectors if more than one. It runs a bit lean most of the time, but as soon as it hits an idle, and the valve overlap is bad, it runs as rich as it can. As long as we're on the topic of too much air, we should also discuss too much fuel. Location: BA, Argentina. Warning Signs Of A Bad Fuel Injector. If your voltage is dropping to the ECM and the power TO the ECM is looking good, try turning on the headlights and watch to see if the measured voltage to the ECM seems to be dropping seriously. Have the same problem? Next problem- You better figure out why it sparks from hood prop to hood. Carbon build-up can cause a clogged or partially clogged injector, preventing the injector from closing all the way.
It seems like I always get the weirdest problems. So if the electric pump in the tank runs, but no pressure, can it be something like a stopped up pump inlet filter in the tank? Southern tier New York. TBI just keeps going. Prolonged fuel starvation can lead to internal engine damage or damage to the catalytic converter. Oh, forgot to ask, OP, is it running now? I'm going to say start with the filter. Not sure where you are buying one for $150 from. TBI works best with the correct pressure - too high or too low, and it all goes drunk. We may be getting somewhere.
I do not believe it was vacuum-referenced. Wow, thanks russell. Other thing to take a look at would be the MAP sensor, if it is outta whack, it'll mess up your fuel requirements too.