No fuel to engine - Toyota 4A-GE 20V

SenatorJones

Ladies and Gents, I'm having trouble starting my '97 AE111 GT (that unholy mix of an E110 and a '97 XLi with a Blacktop in it) and I could use some assistance.

The engine rotates under the power of the starter motor, but the problem is that there is no fuel getting to the fuel rail. I've verified this by removing the fuel line where it meets the rail and turning the key to the ON position, whereupon no fuel comes out of the line. Not a drop.

So, the fuel pump isn't priming and as far as I can determine, it isn't getting power. I don't think it has just failed, as I've swapped it out for a known good unit from my '00 E110 (facelift model, 4ZZ-FE).

I have so far tried the following:

1. Checked the EFI fuses in the engine bay and driver side fuse box - all good.

2. Checked the EFI relay by removing it and energizing the coil with a benchtop 12 VDC supply - all good. Can hear a strong click, and a multimeter verifies continuity between the contacts.

3. Replaced the fuel pump with a known good (if old) unit - problem persists.

4. Checked the car for OBD codes (OBD1) - engine light continuously flashes. This is, apparently, good, but the jury is out on the result, since I've disconnected the battery for extended periods after I found the car wouldn't start, so I'm not sure if the ECU has had a chance to see any errors yet.

5. Jumped the B+ and FP terminals in the diagnostics socket - fuel pump does not come on both when key is in ON and IGN position.

6. Checked any relay I could find, hoping it might be the mysterious and elusive Circuit Opening Relay - all good, except for a flashing relay found in the driver side kick panel, P/N 81980-12110. I'll replace this at some stage.

This last point seems to be the most likely culprit, according to the Internet; failure of the Circuit Opening Relay, which, as I'm sure many of you know, is the second relay in the control circuit for the fuel pump.

I just can't find the buckin' thing. Reports of its location vary from the passenger kick panel to the area around the ECU to the driver side kick panel.

My questions to you:

1. Where is the COR?
2. I understand the AFM is also part of this relay's coil energizing circuit. Could this have suddenly gone dead?
3. Has anyone any other ideas as to why the fuel pump isn't getting power?

Stuff I haven't done:

1. Checked the timing. It could have hopped a tooth, who knows.
2. Ruled out the AFM as the culprit. I've found one guide that indicates how to do this, but it requires use of the COR, which I can't find.

Some further notes;

The car has been sitting up for some time, about two/three months, since it was last driven.
It did occasionally struggle to start, but it got there after <10/15 seconds of cranking.
It appears that the car has been fitted with an aftermarket immobiliser (I didn't know it had one when I was buying it). I have heard of this causing cars not to start after the battery goes flat, but I hadn't suspected that this was the reason for the fuel pump not working since in the past when the battery went flat, the car has started with a jump.

Sorry for the long post, and thanks a million for the help if you can give it. If you need any more information or photos, just shout.

scannerd

hi, don't know that model well, so only thing i can suggest re finding the relay is have look here http://workshop-manuals.com/toyota/, would try to find similar model / wiring diagram to guide you.

if its not the Circuit Opening Relay or AFM then I would suspect bad connect to the fuel pump, check for excessive resistant in the feeds to the pump (see voltage drop testing)

If its definitely lack of fuel then unlikely is immobilizer issue (not common to cut fuel)

jca

Did you try a direct feed from the battery to the fuel pump?

Autochange

does this model have a crank or cam sensor?
Do you have spark?

SenatorJones

Hi All, thank you very much for your advice. In response to your questions. . .

1. I believe I found a diagram that does show the OCR, and its location, but it doesn't actually look like any of the units I've seen in pictures (it's considerably smaller), which I suppose has something to do with the fact that the car is a bizarre crossover model.

2. I did not try a direct feed from the battery to the fuel pump. I did verify that the fuel pump was working outside the car, but I didn't think to run a line directly to it. It would have been the next port of call if removing the immobilizer didn't work.

3. I believe the 20V does have both a cam and crank sensor, and again they were on the list of things to check/replace if removing the immobilizer didn't work.

So, I suppose you may have guessed: I removed the immobilizer and it fired right up. I can't figure out how the immobilizer might have started working all of sudden, but there you go, it can happen.

As it turned out, the immobilizer wasn't as embedded into the cars wiring as I was expecting, with 99% of it being taps into power and signal lines and the final 1% being a splice into *drum roll* the fuel pump power line. So, I removed the whole thing, re-insulated the wire taps and soldered up the fuel pump power line. It started up immediately and I've been spinning around in it since, happy as a clam.

Thanks again, folks!