P38A '97 4.6 HSE engine won't run

Hi all,
It's been a while. My purchase of a newer vogue tdv8 has left the old girl stationary for a few months and now she won't run. Here's what happens: I connect the battery, sync the key and turn the ignition to start. Engine cranks, catches and runs for maybe 2-3 seconds, then dies. It's almost as if the fuel shuts off following the start sequence. She will start again and again, but never keeps on running. Is there a fuel shut-off valve or something I should be investigating? She ran just fine before I parked her up, but she's been sitting outside so I'm thinking it might be something moisture-related. The fuel pump definitely runs the whole time, so it's not that. I guess it could be ignition related, but to me it seems more like it runs out of fuel.
Any tips or ideas? I'm stumped here...

Regards,
Henrik

I've altered my original reply.

Check your fuel pressure. Old tank pumps don't like sitting & commonly fail.

Hi Rick,
Yes, that's on the list of things to check. The pump is only a couple of years old, but the fuel filter is very suspect. It hasn't been changed in ages and there has been very little fuel in the tank. The first time I started her she ran for a few minutes before starting to splutter and finally die. I'm thinking that I was observing the filter clogging up in real-time. I have since added 20l of fresh fuel, but that won't help the filter. I'm hooking up a gauge next, to see what's going on.

Thanks,
Henrik

Hi Henrik!

Have you checked the IACV (idle control valve). Clean valve and after
base idle setup:
http://www.roverparts.com/TechTips/Base_idle_setting_procedure.cfm

Greg

Did you replace the fuel filter?

Filter replaced. Fuel pressure sitting at a steady 38 psi. Still no luck. will check idle control valve. Any other tips? CPS? Will it run at all with a faulty CPS? It ran today, for maybe 3 minutes. It would respond to the throttle, but I was unable to maintain high revs. She cept on rumbling until she finally spluttered and died. Will fire each time, but will not keep running. Fresh battery today.

Thanks,
Henrik

Air flow sensor - failed or somehow not connected.

Thanks Fergie,
Are you sure that could cause these symptoms? I had a Mitsubishi that ran ok without it, at least it idled fine. ls there an easy way to check it?

Henrik

That's a good point, idles not usually affected.

Have you checked to make sure you don't have a large induction leak somewhere.

Try spraying a little carb cleaner about on cranking around the inlet side of things, any leak will become apparent because the engine will burn it and the revs will rise.

Just had a thought. Don't know if its true about this engine but commonly if the ECU doesn't detect oil pressure for a finite period after firing the fuel supply is cut to avoid damage.

I'm sure the more enlightened will be along shortly to confirm if this is the case.

Does it run long enough for the oil light to extinguish?

I'm trying to revive this thread again. After some tinkering, I found that the TPS was reading open circuit and moving the wiper did nothing. Further investigation revealed a crack in the TPS body and there was moisture inside. I finally found a new replacement and installed it today, sure it would do the trick. No such luck, I'm afraid. She still starts right up, runs as sweet as a nut for a few seconds, then dies. I'm starting to think it must be the crank sensor not telling the ecu that the engine is actually running. Has anyone replaced one with the car on the ground? Any tips?

Cheers,
Henrik

Would it run at all with no crank sensor?

Could you take a trace with a Nanocom or similar?

It is almost as if something is blocking the fuel line, like some dirt that is jammed in the pipe and rotates with the flow shutting it off. Can you crawl under, disconnect he fuel pipe and direct into a jam-jar and then bridge the relay and see if it keeps pumping?

I'm trying to find someone with a fault reader who can come and read the codes on site. Not easy and not cheap
I have a pressure gauge on the fuel rail, new pump and new filter. I have no indication that there is anything wrong with the fuel feed itself, but I think something causes the injectors to stop firing. The rev counter works fine, which I suppose is a sign that the CPS is OK?

If you want someone to read codes, it might be an idea to say where you are.

Hi,
Absulutely. I'm in Bergen, Norway, so I don't expect to find too many of my townspeople on here....

Henrik97 said:

Hi,
Absulutely. I'm in Bergen, Norway, so I don't expect to find too many of my townspeople on here....

Click to expand...

Yep, I doubt there will be many people with nanocom or similar there. I do occasionally get to Norway for work but nothing imminent so I can't help you.
Just a thought on this one, years ago, I had a vauxhall cavalier sri (opel vectra to you) and after a head gasket change I had the same problem.
In the end I found that the connector for the temp sender hadn't been replaced correctly. This meant that the ECU thought that the block was infinitely cold and dumped massive amounts of fuel in at startup. So, it would start then flood the engine. If you left it for a couple of minutes, the excess fuel would evaporate and it would start again. If you started it with the throttle wide open it would run and rev itself silly but as soon as you wanted less than 6000rpm it died. Took me hours to find it!

Henrik97 said:

I'm trying to find someone with a fault reader who can come and read the codes on site. Not easy and not cheap
I have a pressure gauge on the fuel rail, new pump and new filter. I have no indication that there is anything wrong with the fuel feed itself, but I think something causes the injectors to stop firing. The rev counter works fine, which I suppose is a sign that the CPS is OK?

Click to expand...

There is a crash reset button. On RHD it is behind the kick panel by the right-leg of the driver. I wouldn't have thought it would have fired at all if this had tripped though.

What does the wiring to the injectors look like? Sometimes they get a bit crackly.

Thanks Wazza, grrr,
Although you make a valid point, I don't think this is my problem as I have no sign that the engine is being flooded.
I will check the crash switch but, as you point out, I wouldn't expect it to fire at all if that had somehow been triggered.

Cheers,
Henrik

Henrik97 said:

Thanks Wazza, grrr,
Although you make a valid point, I don't think this is my problem as I have no sign that the engine is being flooded.
I will check the crash switch but, as you point out, I wouldn't expect it to fire at all if that had somehow been triggered.

Cheers,
Henrik

Click to expand...

Depending on the type of temp sender, it may work the opposite way and send the ECU to the lean end of the spectrum with similar results. I'm not saying it is that but it's an easy one to check and cheap to fix if it is that.
RAVE should have details of what to expect from a multimeter connected to the temp sender and you can trace the signal back to the ECU to make sure its not wiring.
One other suggestion would be to get an old spark plug and connect it to one of the leads and see if you're loosing the spark when it dies. At least then you know if it's fuel or ignition related.

Update:
I have replaced the TPS (which was totally knackered). It didn't do much good, but yesterday she idled until fully warmed. Engine doesn't respond to the throttle, so when I started fiddling with that, trying to get some revs, it died on me and I couldn't get it to idle again. I have a pressure gauge on the fuel rail, and I noticed the strangest thing: When I open the throttle from idle, the fuel pressure rises, which again tells me that the injectors actually stop firing, instead of firing more rapidly. It must be the TPS-to-ECU communication which has a bug of some sort. Does any of you know if the ECU needs fuel-map calibration or something after TPS replacement?

Henrik97 said:

Update:
I have replaced the TPS (which was totally knackered). It didn't do much good, but yesterday she idled until fully warmed. Engine doesn't respond to the throttle, so when I started fiddling with that, trying to get some revs, it died on me and I couldn't get it to idle again. I have a pressure gauge on the fuel rail, and I noticed the strangest thing: When I open the throttle from idle, the fuel pressure rises, which again tells me that the injectors actually stop firing, instead of firing more rapidly. It must be the TPS-to-ECU communication which has a bug of some sort. Does any of you know if the ECU needs fuel-map calibration or something after TPS replacement?

Click to expand...

@wammers question, I'd say. Any corrosion on the pins? Can you check the continuity of the wires from the TPS?