Car Wont Start

[Digilog]

Actually I swtiched the intake pipe over from the orginal motor for the throttle linkage (the JDM was an Auto Tranny)

Kingsoup just pushed open the AFM flapper while I tried to start it and the car ran for 20-30 seconds or so. So I have pulled the AFM out and tested resistance but it all seems to be in spec.

e2-vs 256 ohms

e2-vc 280 ohms

e2-tha 2800 (15-21 degrees)

fc-e1 infinat when closed

fc-e1 zero ohms when open

VS-e2 256 ohms fully closed

vs-e2 61 ohms fully open

I did notice the connector on the harnes is missing the second e2 pinout, but e2-e2 on the afm is zero ohms so I would assume its a redundant pin.

Thanks.

Oh and pulling the cover off the relay in the mitsu was during a return trip to Calgary from whistler through the mountains with limited tools and time in a blizzard.

 

[Digilog]

just a side note, its frustrating trying to search for afm or air flow meter when you can't use a 3 letter word...

 

[jetjock]

I'm curious...what is cranking vacuum?

 

[Digilog]

I don't know, I'll lookup how to test, I am not sure I have a vacuum tester.

 

[Kingsoup]

I manually pushed the flapper open wide, but that didn't work, it was a combination of having it open 3/4ish and the car started to run, roughly but at least it ran.

I think I'm in dire need of understanding how the flapper AFM works and what its role is in the EFI circuit, coming from a GTE car I don't get the N/A system so well.

Whatever it is, the AFM seems to be the problem.

 

[Digilog]

The relay is supposed to do that. Did you check/jumper the AFM switch? The only way of knowing the Mistu relays were bad was to open them up? Yikes. Ever hear of a meter or test light?

I havent had a chance to work on the car tonight but was wondering how do you jumper the AFM and what does this accomplish? Since the car will start and run (roughly) while the flapper is being held open 1/2 to 3/4 of the way, this seems to be the most likely suspect at the moment.

Thanks

 

[jetjock]

Cranking vacuum can be measured by installing a vacuum gage on the manifold, pulling the EFI fuse, and cranking. Leave the throttle closed when doing it.

The vane afm is nothing more than a potentiometer that supplies 0 to 5 volts between E1 and Vs. It also includes a thermistor for measuring ambient air temp and a switch for the fuel pump that closes when the vane opens. Based on the readings you took it seems to be OK but I'd check it by measuring voltage. You can also unplug it and try starting the car. The ECU will use a default value in that case but the TPS must be working right (no code 51) for it to happen.

Frankly I doubt your afm is at fault but clear any codes before doing this.
That way you can check for afm codes when it's unplugged. The point of that is it's a quick and dirty way of verifying the wiring between the ECU and afm is intact.

 

[Digilog]

So I unplugged the AFM and the car will start. It runs for 10-15 seconds and dies. But I can restart over and over now... wtf.

I got code 24 after AFM was pulled.

So I guess I am closer.

I have yet to have a chance to get a vacuum gauge.

 

[supramacist]

Dis-connect the battery for around 15 minutes.

Plug in the afm. And try codes once more. See what you get.

Don't hit the throttle while pulling codes or you'll get the 51 into this noise.

 

[Digilog]

Ok discoed the battery, plugged int he AFM no Codes.

Car tried to start once then nothing, basically its much worse with AFM plugged in.

 

[supramacist]

So it's worse with it on and still no codes???

That doesn't jive man.

I would order in a new afm from O'rielly's and put it on and just try it.

Pay the dang core charge and everything and put it on.

If it doesn't work it cost you an hours worth of labor and an overnight wait.
To know that is NOT the problem. Vaf's are tricky.

If it clears it up..., solid. if not..., take it back.

Hope this helps.

 

[Nick M]

The AFM can give a really bad signal, but not be out of code setting range. Such as some monkey took the cover off and loosened the spring.

But even if it is really loose and rich, it should still start, just with a lot of smoke.

Are you sure you have injection pulses and spark?

 

[supramacist]

Some people have to be made believers.

Solid responce Nick.

 

[jetjock]

Sigh. Or he could test it the way I said. There's nothing tricky about these things at all. Put a damn meter between ground and Vs and with the key on push the vane from full closed to full open and note the voltage. If he's smart he'll measure at the ECU connector. I swear, it's like talking to an amoeba...

 

[supramacist]

Can we get some pics of the connector?

 

[Kingsoup]

Sigh. Or he could test it the way I said. There's nothing tricky about these things at all. Put a damn meter between ground and Vs and with the key on push the vane from full closed to full open and note the voltage. If he's smart he'll measure at the ECU connector. I swear, it's like talking to an amoeba...

Ok buddy, you are getting annoying in all these posts of yours, we are not idiots, we've both been working on a lot of vehicles nonstop for 10yrs. I've done 10+ motor swaps on Supras alone, give a little bit of credit, if you aren't going to be helpful then piss off. I don't care if you are a self proclaimed expert, your arrogance is not helpful and if I wanted to deal with self-important douches I'd goto Supraforums.

The AFM can give a really bad signal, but not be out of code setting range. Such as some monkey took the cover off and loosened the spring.

But even if it is really loose and rich, it should still start, just with a lot of smoke.

Are you sure you have injection pulses and spark?

I've verified fuel pump operation, rail pressure, and the injectors seem to fire but only when the AFM is unplugged. The plugs are good and sparking, timing is perfect, the electrics are all grounded and we're not throwing any codes.

All I can tell is that it will run roughly for a bit when the AFM is disconnected then die, even though it tested the AFM per TSRM spec it seems something. I've done a lot of swaps and never had this much trouble tracking the problem down, I wish it was more obvious. I've searched on celicasupra, supraforums, Mania, Celicatech, gt4forums for all of these things and although have found many similar situations, no solutions that seem to match.

So frustrating this! Even more frustrating when we are belittled in our support thread.

 

[jetjock]

What's getting annoying is my giving you advice and you being too stupid to follow it. Perhaps you missed that part where I said a no start on these cars is one of the easiest problems to solve. As for working on cars non-stop for 10 years your "support thread" is filled with post after post showing you haven't a clue how the car works or what you're doing. The fact is you *are* idiots so here's my last piece of advice before pissing off: Open the friggin' manual and try reading it...

 

[Nick M]

Sigh. I swear, it's like talking to an amoeba...

Amoeba's don't talk back. :biglaugh:

I've verified fuel pump operation, rail pressure, and the injectors seem to fire but only when the AFM is unplugged.

I don't recall seing a car with spark and no injection get fixed by changing an airflow meter due to faulty readings. But with our pump switch inside it, it could happen. If Jetjock has data indicating this does that, than it is so. But why don't you do the test he told you? While I haven never met him, his knowledge is as good as anybody I know. Well, a couple of people on here are pretty good.

The R2 resistor( connected in parallel with R1) allows the meter to continue to provide a signal in the event that an open occurs in the main potentiometer(r1). The Vane airflow meter also has a fuel pump switch built into the meter that closes to maintain fuel pump operation once the engine has been started.

JJ, what closes the fuel pump switch? The flapper door? Even though he said he has pump operation.

 

[jetjock]

Amoebas also apparently don't have a clue about EFI systems or how to do electrical testing. Yes, the switch is controlled by the vane. Just to be clear I never said the root cause of his problem is the AFM, just that he's so tunnel visioned on it I was stating how the air flow part could be checked.

Appears he'd rather throw parts at the car and search forums for solutions rather than systematically troubleshoot though. That's to be expected from someone who, rather than having 10 years of experience, has 1 year of experience 10 times. Ah well, he'll eventually get it fixed. Not with my help though...

 

[johnathan1]

The car should still start just fine with the AFM unplugged...so doesn't that mean that the problem is elsewhere?

This should help you:

http://www.cygnusx1.net/Supra/Library/TSRM/MK3/manual.aspx?S=FI&P=12