bad fpr? - Page 2

3.0trd · 04-24-2008, 01:50 AM

one other test, I pulled the connector off the injector solenoid resistor, and did an impedence test, I got 8 ohms for 10 and 30, but no signal for 20... ( I believe its injectors 3 and 4)

3.0trd · 04-24-2008, 01:52 AM

the injectors are green, why?

cre · 04-24-2008, 03:31 AM

I asked the color because in '89 there were a number of changes made to the MKIII electrical system, including the N/A's injectors. You will find on occassion a '89 with part '88 wiring and part '89+ wiring. If they were yellow the resistance specs would be the same as the GTE's.

Anyway, I'm not convinced it's the injectors. Even if 4 were out it would still buck and cough when cranked.

You're not getting any error codes? You've tested the fuel pump relay and resistor pack? Have you double checked the AFM's connection? The car does have gas right (this did happen to someone before... broken gas gauge)?

I am suspicious of the fuel pump, you should grab a pressure testing kit and check it...

OR you can do it low tech style (don't assume I recommend this method.. you do it and screw it up it's your problem.. I accept no responsibility): Disconnect the fuel feed line, connect a hose to it. Run the hose to a bucket off to the side of the car. Wrap a damp towel around the union (to prevent fumes from escaping). Now, with someone holding the hose in the bucket jumper FP and B+.... got fuel?

3.0trd · 04-24-2008, 03:29 PM

I haven't checked for error codes, I'm looking at the tsrm right now to figure out how to check them. and I just might try that pressure test method.

3.0trd · 04-24-2008, 07:10 PM

alright, checked error codes, 51, looks like the only one.

3.0trd · 04-24-2008, 10:42 PM

so I did some very advanced testing (pulled fuel line off, jumped fuel pump) and, yeah, no fuel whatsoever... but with the jumper wire in, if I go to the filler neck, I can hear the pump working. apparently there is no flow though. could it be the pump? and still no noise under the hood when I jump the pump.

cre · 04-24-2008, 11:50 PM

You are aware that the fuel pump is IN the fuel tank, right? If you hear it from the filler neck it's probably not the problem unless the impeller broke free... in which case there's usually a little extra clatter.

If you're getting no fuel from the line your possibilities are:
Fuel pump (you could use an ammeter across FP and B+ to see if the pump is actually drawing power)
Clogged fuel filter
crush or blockage in the fuel line

If it's the filter or the pump it's usually easiest to pull the tank and replace both at the same time.

3.0trd · 04-25-2008, 12:04 AM

so, with the key on, the fp- b+ should have 12 v, or do I use an ohm reading?

cre · 04-25-2008, 12:18 AM

Nope... Across B+ and the battery's ground there should always be 12v with the ignition in the on position.

To read current draw you need to set the meter for 10A, connect the leads in the correct locations on the meter (it's usually got a different plug for the positive lead), set the meter to 10A (or higher if depending on the meter), then you place the + lead in the B+ position and the - lead in the FP location, the meter will act as a jumper. The pump should start up and the meter will display the amperage being drawn... if I mixed up the + and - positions it'll show the amperage as -5.3A (or whatever), it's not an issue though.

If the coil in the fuel pump is shot the amperage will be very little or 0. If the pump is seized the amperage will be high.

And of course, I don't recall what the specs are supposed to be if it's good... :P

3.0trd · 04-25-2008, 03:37 AM

turns out I'm just retarded... while attempting to change the fuel filter, the filter ended up twisting, pinching off the line from the tank to the filter... anyway, I fixed that and now it runs like a champ. god I feel retarded. my new problem is I have no turn signals or hazard lights. I'm gonna start with the blinker relay, but any other ideas? the headlights go up and down, I have brake and normal tail lights.

04-24-2008, 01:50 AM	#11
3.0trd 3" Exhaust Join Date: Mar 2008 Location: Cali Posts: 76	one other test, I pulled the connector off the injector solenoid resistor, and did an impedence test, I got 8 ohms for 10 and 30, but no signal for 20... ( I believe its injectors 3 and 4)

04-24-2008, 01:52 AM	#12
3.0trd 3" Exhaust Join Date: Mar 2008 Location: Cali Posts: 76	the injectors are green, why?

04-24-2008, 03:31 AM	#13
cre Toyota Racing Development Join Date: Apr 2007 Posts: 5,038	I asked the color because in '89 there were a number of changes made to the MKIII electrical system, including the N/A's injectors. You will find on occassion a '89 with part '88 wiring and part '89+ wiring. If they were yellow the resistance specs would be the same as the GTE's. Anyway, I'm not convinced it's the injectors. Even if 4 were out it would still buck and cough when cranked. You're not getting any error codes? You've tested the fuel pump relay and resistor pack? Have you double checked the AFM's connection? The car does have gas right (this did happen to someone before... broken gas gauge)? I am suspicious of the fuel pump, you should grab a pressure testing kit and check it... OR you can do it low tech style (don't assume I recommend this method.. you do it and screw it up it's your problem.. I accept no responsibility): Disconnect the fuel feed line, connect a hose to it. Run the hose to a bucket off to the side of the car. Wrap a damp towel around the union (to prevent fumes from escaping). Now, with someone holding the hose in the bucket jumper FP and B+.... got fuel?

04-24-2008, 03:29 PM	#14
3.0trd 3" Exhaust Join Date: Mar 2008 Location: Cali Posts: 76	I haven't checked for error codes, I'm looking at the tsrm right now to figure out how to check them. and I just might try that pressure test method.

04-24-2008, 07:10 PM	#15
3.0trd 3" Exhaust Join Date: Mar 2008 Location: Cali Posts: 76	alright, checked error codes, 51, looks like the only one.

04-24-2008, 10:42 PM	#16
3.0trd 3" Exhaust Join Date: Mar 2008 Location: Cali Posts: 76	so I did some very advanced testing (pulled fuel line off, jumped fuel pump) and, yeah, no fuel whatsoever... but with the jumper wire in, if I go to the filler neck, I can hear the pump working. apparently there is no flow though. could it be the pump? and still no noise under the hood when I jump the pump.

04-24-2008, 11:50 PM	#17
cre Toyota Racing Development Join Date: Apr 2007 Posts: 5,038	You are aware that the fuel pump is IN the fuel tank, right? If you hear it from the filler neck it's probably not the problem unless the impeller broke free... in which case there's usually a little extra clatter. If you're getting no fuel from the line your possibilities are: Fuel pump (you could use an ammeter across FP and B+ to see if the pump is actually drawing power) Clogged fuel filter crush or blockage in the fuel line If it's the filter or the pump it's usually easiest to pull the tank and replace both at the same time.

04-25-2008, 12:04 AM	#18
3.0trd 3" Exhaust Join Date: Mar 2008 Location: Cali Posts: 76	so, with the key on, the fp- b+ should have 12 v, or do I use an ohm reading?

04-25-2008, 12:18 AM	#19
cre Toyota Racing Development Join Date: Apr 2007 Posts: 5,038	Nope... Across B+ and the battery's ground there should always be 12v with the ignition in the on position. To read current draw you need to set the meter for 10A, connect the leads in the correct locations on the meter (it's usually got a different plug for the positive lead), set the meter to 10A (or higher if depending on the meter), then you place the + lead in the B+ position and the - lead in the FP location, the meter will act as a jumper. The pump should start up and the meter will display the amperage being drawn... if I mixed up the + and - positions it'll show the amperage as -5.3A (or whatever), it's not an issue though. If the coil in the fuel pump is shot the amperage will be very little or 0. If the pump is seized the amperage will be high. And of course, I don't recall what the specs are supposed to be if it's good... :P

04-25-2008, 03:37 AM	#20
3.0trd 3" Exhaust Join Date: Mar 2008 Location: Cali Posts: 76	turns out I'm just retarded... while attempting to change the fuel filter, the filter ended up twisting, pinching off the line from the tank to the filter... anyway, I fixed that and now it runs like a champ. god I feel retarded. my new problem is I have no turn signals or hazard lights. I'm gonna start with the blinker relay, but any other ideas? the headlights go up and down, I have brake and normal tail lights.