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Hello Everyone, after reading hours of previous posts I am still baffled by my situation. The car starts fine when cold, once up to operating temp. it will not re-start, it cranks but won't fire. This does NOT happen every time so when I take it to the shop, of course it starts right up. We have changed the fuel pump, fuel pump relay, fuel pressure regulator to no avail. The only code is 3-1-5 on A2(EVAP). We are now going in to the sensors, but shouldn't they come up on the codes? There is spark when this happens, fuel pressure but not a lot of fuel in the rail. It all most seems like something is telling the pump not to run. Any ideas?
Thanks In Advance
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posted by
someone claiming to be cbe_steve
on
Sun May 23 01:01 CST 2004 [ RELATED]
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hello,
i cant fully make sense of your thread.you say there is fuel pressure but not much fuel in the rail,so where are you measuring your fuel pressure at? the normal place to read from is the valve on the end of the rail,should be around 30-40 psi when cranking.if there is pressure there then pump and wiring and lines are not your problem.you can also remove (carefully) the entire fuel rail with injectors attached and reconnect it to the fuel lines,place a shallow plastic container underneath and get someone to crank the car and see if fuel sprays out or not.if the car does not start from lack of fuel as you obviously think then try jump the fuel pump with a 12v battery to make it run and see if it starts up then,or crank the car and spray engine start into the air intake (remove lid of air filter box) just to see if it fires up.this would confirm weather its lack of fuel or not.
if still no go then recheck for spark,recheck no other fault codes,and then remove plugs and do a compression test.these model engines had notorious problems with sticking lifters and valves which cause lack of compression and therefore no start,the comp test would show this.the symptoms of the low/no compression were intermittant no start, then if left for 10min they would usually start up again.
hope this helps.
steve.
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Hi Steve, I had the mechanic from the shop I deal with come look at the car when it wouldn't start. He checked the valve at the fuel simply by pressing pressing on the valve he said not as much fuel came out as he would have of thought. Can you use a regular pressure gauge to check the pressure? We did do a compression test and I did have one cylinder low on comp. but they said they cleaned it and the comp went up. I like your idea of jumping the fuel pump with another battery, do you know what wires to hook up?
Thanks
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posted by
someone claiming to be don
on
Sat May 22 07:17 CST 2004 [ RELATED]
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this is almost a classic symtom of clogged fuel filter, or excess vacuum in the tank maybe.... or fuel injectors leaking and flooding engine, wiring to pump ...or ..........
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Which relay did you replace?
The fuel pump relay (103) is in the fuse box (you need to remove the whole lid)
Not the one on top of the radiator.
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Thanks for the responses, We did replace the fuel filter when we changed the pump(for warranty) The fuel pump relay we changed was 103 under the fuse box. Weve checked fuel pump wiring and it seems ok. The plugs are dry when it happens it just seems like the pump is not running. Wait a few hours and everything is fine?
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posted by
someone claiming to be Chrissij
on
Sun May 23 16:00 CST 2004 [ RELATED]
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I'd be going in the same direction as VOBD, the system relay under the cowl behind the radiator..check that for proper operation when your car is not starting. If it's not clicking, well then there you go (or don't go). Also, I've had problems with the funky polybutyl insulators for the wires in the connector to this relay fall apart...the wires then touch together at or in the connector.
Barring this being the problem, are you absolutely sure that you have spark when your car won't start? If that relay, and those connectors are fine, I usually lean towards cam sensor when I have a customer with a similar problem.
Chris
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Hi Chris, we haven't checked that relay, I'll be sure to mention it to the mechanic. We are sure we have spark when this happens because the mechanic left a seperate plug and wire to plug into the coil when it won't start. He then had a chance to check all the plugs when it wasn't starting and said they were all good. We are thinking about changing the coolant temp sensor as I had trouble with the car heating up properly in the winter and the fan doesn't seem to hit high speed. What do you think?
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posted by
someone claiming to be Chrissij
on
Mon May 24 16:33 CST 2004 [ RELATED]
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Well, yes, I think you most likely need an ECT sensor. Check A7 for codes in the combined instrument. Often times you'll find a 122 there even if A2 didn't alert you to a possible problem. Yes, a faulty coolant temp sensor can keep you from starting, but...you said the problem occurs when the engine is warm in a "restart" situation. You also said that you suspected "low" fuel pressure...these two don't go together. If the ECT is telling your ECU that your engine is not warm when it is, the resulting problem would be TOO MUCH fuel, not too little. The engine would flood, and you would be unable to start the car until the plugs dried out.
If you have spark, and you have fuel, you obviously have one of them that is not up to snuff. You have a new "Volvo" pump? You have spark to ALL the plugs? When you pull a plug...is it white tipped (lean) or black (rich)? If you unplug the air mass meter, will the car start? We've had problems with the flapper on the airbox getting stuck shut and heating up the air mass meter.
I'd also check all my body grounds, a weak ground will lead to a hot sensor.
Chris
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Well I got the car back today after they replaced the coolant temp sensor. Everything was going fine until I went to go after idling at a light and it stalled, I rolled to a stop and it wouldn't start again. I pulled out the auto trans ECU and put it back in, both ECU's seemed very hot. Not sure what to do next? I am thinking the RPM sensor because I was moving when it stalled. Anybody have an answer??????? After about 20 min. I put the ECU back in and it fired up, coincedence??
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posted by
someone claiming to be Chrissij
on
Sat May 29 03:51 CST 2004 [ RELATED]
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I didn't think the ECT would fix it, but from what you said it was needed anyway. You realize it could be so many things...
I don't think pulling the ECUs did anything except allow you to at least do something and feel less vulnerable to the whims of your car. Any component will fail when the car is moving, as all of the sensors are doing their job whenever the car is running...be it cruising down the highway, or sitting at idle. The fact that you were slowing to a stop, thus indicating something that may be affected by a shift of a wire, or a shift of the fuel, I would look at the relay under the cowl, and I would look at the connections to my air mass meter, my crank sensor, and my cam sensor. I would also fill up my car to see if the problem only occured when I was under the half a tank mark.
Chris
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Hi Chris, Thanks for the input. One of the things I am noticing is the car seems to hit its operating temperature quickly, faster than ever before. Would this have anything to do with the transmission heating up. I am taking it in for a tranny flush, (it's due) My thought is that the tranny is getting hot enough to affect the RPM sensor reading, therefore shutting down the fuel system. Normally the temp gauge would sit at 1/4 but it goes right to 1/2 or a little above right away. I did clean a body ground and it hasn't happened again since, but we haven't drove enough to tell if the problem is gone.
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posted by
someone claiming to be Chrissij
on
Wed Jun 2 16:12 CST 2004 [ RELATED]
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You most likely also have a new thermostat, with that new coolant temp sensor...what you were experiencing was most likely a stuck open thermostat. No, I don't think your problem is going to have anything to do with your transmission heat. You said that when your car doesn't want to start that you have spark, if the problem were the rpm sensor, you wouldn't have spark. Have you checked that front relay and the wires in the connector to that front relay yet? The cleaning of the body ground could have fixed it...I've had ground problems kick my fanny on numerous occasions.
Chris
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Hi Chris, it is my understanding that the RPM sensor sends a signal to the ecu to keep fuel system relay energized. The Relay stays energized until that signal is lost. This is to prevent the fuel system to run in case of an accident, the relay de-energizes and shuts the fuel system off. There is a couple of relays above the rad I checked the connectors and they look fine. I do not know which one is the fuel system relay. COuld you give me an idea of which one? Thanks again
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