been a while since an issue - Toyota Nation Forum : Toyota Car and Truck Forums

InfInIty13X · 03-11-2011, 07:08 PM

It's been a while since I posted about my Prizm. The last time I was here I was rebuilding the bottom end after the timing belt tensioner failed. Everything has been going good the past 14k miles. I'm now at 260k+. The cylinder head still leaks oil into the chambers I believe because the knock has come back to an extent. I have to use 93 octane again. It burns off oil leaking past the guide seals until it heats up & expands. It doesn't do it on warmer days either. The oil leak is making me burn oil AND knocking. I deal with it because I can't afford head work.

Anyway the only real problem I'm having now is what I believe to be the fuel pump. The past couple of days the car has been slow to crank but always started. Today it died as I was pulling out of my apartments for work. I checked the battery and it had 12.4V. I put another battery in from my Isuzu that read 12.2V and it still didn't start. I know the battery is good because it cranks up my Impulse no problem.

The ignition module is good I'm assuming because I measured battery voltage between the +/- coil terminals. Continuity from coil + to ground was ~0.8 ohms. Besides all that... I pulled #1 plug wire and it sparks during cranking when grounded.

The pump doesn't prime @KEY-ON. I noticed there was no fuel pump fuse/relay but just the EFI fuse/relay. The relay clicks @KEY-ON and the fuse isn't blown. I'll backprobe the pump wiring to see if I get anything. I'm thinking the pump started going out and pulled a load on the current which was causing my slow cranking and now the pump has finally died out. The car spins over fine.

tl;dr

Fuel pump won't prime. Are there any other things I'm missing on this car? This pump has four wires in the connector but the Chilton's online diagram only shows two. Otherwise I have to assume it is just a bad pump.

InfInIty13X · 03-11-2011, 08:14 PM

Okay so I just tested the pump at the blue/black wires and white/black wires. I got no voltage @KEY-ON and about 10.4V cranking. Any thoughts?

NWMO 95 Prizm Lsi · 03-11-2011, 10:15 PM

Infinity,

I'm new to the game, but just changed the fuel filter on my Prizm. The Haynes discussed a fuel pump relay that is located behind the stereo. I would actually have to remove the stereo and surrounding dash to get at it.

10.2V sounds low, but check at the battery while you are cranking. If you have the same at the battery and pump, electrical may be ok.

Guage for the fuel rail to measure pressure? Should be able to pull a plug and see if you are getting fuel.

Chris

InfInIty13X · 03-11-2011, 10:35 PM

Quote:

Originally Posted by NWMO 95 Prizm Lsi

Infinity,

I'm new to the game, but just changed the fuel filter on my Prizm. The Haynes discussed a fuel pump relay that is located behind the stereo. I would actually have to remove the stereo and surrounding dash to get at it.

10.2V sounds low, but check at the battery while you are cranking. If you have the same at the battery and pump, electrical may be ok.

Guage for the fuel rail to measure pressure? Should be able to pull a plug and see if you are getting fuel.

Chris

The relay you speak of is a fuel pump relay. I completely forgot about that one. It is normally removed for relieving pressure before opening the fuel system. The 10.4V is normal "to me" because in my experience the system usually drops a few amps between KEY-ON and START because of the high load the starter draws. As for the pressure gauge... I live in Houston. You'd think SOMEONE had a rental I could scoop up but here we are...

InfInIty13X · 04-05-2011, 02:20 PM

I finally got the fuel pump in the mail this weekend and installed it today. She took a little coaxing but after installing new plugs she chuggled to life. I'm only uneasy about my pump wiring. I had to snip the old sender assembly wiring to accept the new pump wiring. I crimped on some butt connectors and wrapped them in electrical tape. I have no idea how long it will hold but what is important is I have my DD running.

I love my Isuzu and all but that stiff suspension is not fun on Houston roads.

InfInIty13X · 04-05-2011, 07:54 PM

I'm still alive... barely. Everything thing was fine; totes more throttle response now. Everything was kosher until I was pulling out of Kroger and it nearly stalled out in the middle of the road. I could not duplicate it afterward either.

Bitter · 04-05-2011, 08:00 PM

quick left hand turn?

InfInIty13X · 04-06-2011, 06:36 PM

No I was actually pulling out from a grocery store parking lot. Now the car is dead again. Today it started stalling in traffic and as I would load the motor from low rpm/idle. It was missing at idle too at what seemed like steady intervals. I actually stalled on the interstate. Thank goodness traffic was backed up and slow moving.

I pulled the plugs when I got home and the electrodes are white but not wet with fuel or oil. I changed the wires today but cannot get it to start now. I did once and the exhaust smelled very rich. It didn't miss during idle but it was idling higher since the motor cooled down. My friend revved it up some and then loaded the motor WOT which killed it. Now when I crank it with the throttle wide open it tries to start but won't and sends black smoke out through the air filter housing.

InfInIty13X · 04-06-2011, 07:16 PM

Okay I got it started again using the clear flood mode method. I let it warm up to temperature and loaded the motor near WOT at idle and it died again. Any thoughts?

Bitter · 04-07-2011, 07:22 AM

sounds like a bad fuel pump, volume or pressure is lacking. Was there debris in the tank? I once had about 3 cups of white powder at the bottom of mine for some reason, once I sucked it out it was OK.

InfInIty13X · 04-07-2011, 08:33 PM

Now I can't get the car to start.

I did earlier today but not now. I rented a hand vac pump and fuel pressure gauge for testing the FPR/EGR but can't really use it yet. I pulled a plug and it was quite fouled out with fuel. I tried starting it with the vac pump removed but nothing. I'm going to try again here in a few after the cylinders wash down.

I'm about ready to buy a scan tool from O'Reilly that gives me live data. I'm tired of this.

Bitter · 04-07-2011, 10:46 PM

try starting it with the throttle about 1/2 open.

blb · 04-08-2011, 12:08 PM

.

Sounds like the classic symptoms of a bad fuel pressure regulator.

.

InfInIty13X · 04-08-2011, 01:50 PM

Well now I have no spark. Pulled plugs #1/#2 and nothing. This car is possessed I swear it.

InfInIty13X · 04-11-2011, 02:24 PM

Okay so I have:

tested and found battery voltage between coil + / ground and coil - / ground
test light on ground / coil - flashed when engine was cranked
resistance between coil + / - was about .8 ohms
battery voltage read about 10.5V at coil + / ground when engine was cranked
tested and found battery voltage at ICM coil signal wire with key-ON
about 8V read at ICM coil signal wire when engine was cranked
tested the Hz coming out of the igniter while cranking the motor; this went up to .04 Hz and stayed there

My textbook tells me that voltage at ICM coil signal wire should be over 10.5V when cranking. It was not. Does anyone have any suggestions on testing these igniters or any experience with them? I'd rather not sink $200 on a non-returnable part that "might" the problem.