Fuel injectors not firing ?

[Guss]

After filling up with gas today car started intermittently missing and loosing power, straight away after leaving pump for 5 sec then nothing for 5min then another 2-3 sec whilst boost'n up .

By this time i'd noticed that the lack of power was acompanied by the A/F gauge going full lean and was heading home.
It then started doing this at the lights, rpm drop a/f goes full lean car barely runs but cleared as i pulled away.
Came back with vengeance on its mind and stranded me on side of road, car still ran but with no proper fueling i wasn't going no where.

Checked all wiring i could get to, ballast, firewall grommets, fuses etc nothing appeared damaged or loose.

Engine is 3S-GTE, Link LEM V1, 2 banks of 4 injectors(4 rolla,4 3S)

What should i check first? I cant easily access the injectors without pulling half the car apart.

could it be water in the fuel? right after filling up, water sinks in petrol right?

[RedMist]

Fuel pressure, either pump or filter related.

[mjrstar]

grab a hand controller and see if it's the injector duty cycle tapering off then you'll know it's a signal the ecu has recieved..could well be a crank angle sensor with a bit of moisture giving an odd signal from time to time???

[RedMist]

What the heck is a "hand controller"? and how do you tell on said hand controller that the injector duty cycle is tapering off?
Crank angle sensor is a possibility. But from the description of your problem pump or filter is a greater probability. Just get your fuel rail pressure tested.

[mjrstar]

he said he is using a link ecu, the hand controller is the non laptop controller (hand held) which is able to display engine parameters such as duty cycle and other useful stuff...

i hope this clarifies what i was trying to say, this is a useful diagnostic and tuning tool for those of us with link ecu's.
although as redmist has said it could well be a fuel pressure problem ie: f.p.r or pump/filter issue.

[Guss]

checking fuel pressure is definitely first on the list, anyone know where to get a cheap pressure gauge with fuel safe seals?

If it's the fuel pump wouldn't it only have an affect during high demand not at idle.
I could understand if it was a persistent problem (pump shagged) but as comes and goes i find it hard to understand how the pump could be causing the problem.

I've got a PCLink so i'll borrow a laptop and have a look for any thing funny.

I did have to jump start the car with a spare battery, could the voltage spike from disconnecting the battery while engine running fry the ecu?

[matt dunn]

Cheap easy way to check the fuel pressure is to pull off the return line to from the regulator.
Give it a flick on the starter, if fuel comes out the pipe, it has pressure.

Never seen a faulty OE regulator so it's a pretty reliable test.

matt

[mjrstar]

i had a similar problem which ended up being a bad power source(6 year old battery), as you've had to jump start it already how about borrowing a good battery, it's a lot easier than flow testing pumps etc. with the problem at idle it would be where the alternator has the least chance of being able to keep up with power demands.
as for fuel flow you can set the link to pump fuel without the engine running ( hold down the up and down buttons on the hand controller it displays something like fuel test??) then pull the hose off the return side of the fuel rail, put a container coming off this, if your'e getting at least a litre/minute out here it's probably not going to be a fuel supply isse.
there is probably a way with the pc link to 'trick' it into turning the pumps on without the engine turning over although i have not tried this...

[RedMist]

i had a similar problem which ended up being a bad power source(6 year old battery), as you've had to jump start it already how about borrowing a good battery, it's a lot easier than flow testing pumps etc. with the problem at idle it would be where the alternator has the least chance of being able to keep up with power demands.
as for fuel flow you can set the link to pump fuel without the engine running ( hold down the up and down buttons on the hand controller it displays something like fuel test??) then pull the hose off the return side of the fuel rail, put a container coming off this, if your'e getting at least a litre/minute out here it's probably not going to be a fuel supply isse.
there is probably a way with the pc link to 'trick' it into turning the pumps on without the engine turning over although i have not tried this...

I wouldnt hold both the up and downarrows on the link tuning module. I'm pretty sure thats a reset.

Links are notoriously power sensitive. A bad battery is a possibility, however every time I've had battery issues with my Links its never fired fullstop.
He has a Link LEM V1, its not PC Link compatible. However he can run a serial link through to either that rubbish old Link DOS based program (ComLink??) or any terminal emulator to log data only. I think the V1 is 1200, n, 8, 1 . Logging data from the V1 will give you % fuel flow and batt voltage which may assist in your diagnosis. The only way for you to get a fuel pump test is on the Link Tuning Module. Edit - Up arrow?? The LEM wasnt PCLink compatible until V5.

[piw]

The LEM wasnt PCLink compatible until V5.

V4 was the first PC compatable one.

[RedMist]

The LEM wasnt PCLink compatible until V5.

V4 was the first PC compatable one.

Having a bad day. Your right. I had a V4 on my 4age and it was PC Link tunable. The V3 I had on my 20 Valves I used to use WAR Motorsport software... for logging and map display only. No PC tuning.

[Guss]

And i was wrong i have the v4 and a serial link, so will get a laptop this weekend.
will also try pulling the return line off to check 4 pressure when it next occurs.

personally i think it's electrical as the pump is fairly new 'hope its not chinese ripoff'.
that also better explains the intermittent behaviour.

[Guss]

Well i finally got the car out and about today (bloody wet weather).

Plugged the laptop in, all looked ok no funny business and good voltage the whole time.

Flowed the pump, got well over a couple liters a minute.

Took it for a drive, no missing no coughing nothing. drive around some more, nothing. drive like an idiot for about 1/2 hr , no problems and still have licence.

Question is how would water in the fuel make the car run ?
I haven't really changed anything and the problems gone away, I really want to believe it was water as that makes it a really easy fix.

gav