Car wouldn't start today...fuel system questions
Posted 14 December 2018 - 08:43 PM
Finally got my quest smogged and was running well...then today I parked it, ran inside, ran back out, and it wouldn't start
The engine turns over...it has spark at the coil for sure...so i'm assuming it's not getting fuel..
Excuse my naivety with these questions..
I should be able to unscrew the fuel feed into the Throttle body, turn the key on so the pump primes (but not start the car) and gas should come out of that line correct? Hoping I can use this as a quick test to see if the fuel is making it into the TBI
Posted 14 December 2018 - 09:30 PM
Edited by markhansenconquest, 14 December 2018 - 09:33 PM.
Posted 14 December 2018 - 10:08 PM
When the key is turned to the START position the fuel pump is energized... then when the ECU sees ignition pulses (same pulses that drive the tachometer) it "knows the engine is still running" and the ECU maintains power to the fuel pump.
So for your test just turning the key to the ON/RUN position won't prove squat. Instead, reach down and unplug the smaller wire feeding the starter solenoid to disable the solenoid. Then undo the fuel RETURN hose from the fuel pressure regulator - the half-inch hose clamped to the regulator at the top/front of the throttle body. Run a spare hose from the regulator to a bucket or gas can (and tape it or zip-tie it because it'll try to flair about) and turn the key to the START position. See if you have fuel flow.
There is also a fuel pump test connector in the wire bundle by the air filter canister and passenger side fender. Look for a wire and connector hanging from that bundle, or taped to the bundle. It'll be a single black+white wire... there's also a 2 or 3 wire "dead-end" connector there too but that's something else - ignore it. Run a beefy jumper wire from the battery positive post to that black+white wire to "hot wire" the fuel pump. The pump will run regardless of the ignition key position. Expect a few sparks when you make this connection... which is also why I suggest connecting the battery end first so that the sparks happen away from the battery and the hydrogen gas (think Hindenburg) that accumulate around lead acid car batteries being charged/recharged.
One thing about leaking fuel injectors: as they leak they flood the engine. The car will be hard to start 20 minutes or so after a shutdown... but wait a day or two (that flooding evaporates) and it'll start and run decently again. While doing the black+white jumper wire test, remove the fat air hose feeding the throttle body... shine a flashlight in there and look at the injector tips. If you see ANY gas spraying or dribbling from either injector tip you've found a bad injector. Maybe cleaning it (spray carb cleaner through the injector while using a small 9 volt battery to open it - once you remove it from the car... and don't use the car battery to power the injector as that WILL fry it) will save it... or you may have to send it to an injector cleaning/repair company.
Usually fuel pump issues manifest themselves as a car that will start and run normally at first but after a bit of driving it'll buck or run poorly when you try to accelerate... and the longer it is driven the worse and worse it gets. Basically, worn fuel pumps get hot and that heat causes internal thermal expansion until the pump starts jamming... fuel flow and fuel pressure drop and the engine struggles to run on less and less fuel... eventually the pump jams completely. If you can hear a nasty sound when doing the black+white wire jumper trick (especially with the gas cap off) that's a warning sign of a near-death fuel pump.
Posted 14 December 2018 - 10:17 PM
Edited by croquest87, 14 December 2018 - 10:44 PM.
Posted 16 December 2018 - 08:47 PM
Posted 17 December 2018 - 06:27 AM
Posted 17 December 2018 - 05:38 PM
Posted 17 December 2018 - 07:36 PM
Posted 17 December 2018 - 08:51 PM
Here you go
Fuse links https://imgur.com/a/mEBoRGM
Third one from left(brown)
You can swap in let's just say red one in and see if your car starts. Note: do not leave it in permanently you must replace it w brown one.
Edited by croquest87, 17 December 2018 - 08:56 PM.
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