1999 C70 intermitent crack no starts

volvooh · Post by **volvooh** » 09 Sep 2016, 08:10

1999 C70, 140,000 mi. Last night I went to start it, got crank but no start. I checked for CEL's and have none. This morning, it starts right up. I have had occurrences this past summer where it would have hard starts (several cranks). This is a summer car that is only driven between May and October.

I thought it might be a crank/cam sensor, but there are no codes. Also, it happened when the engine was cold. Maybe fuel delivery (fuel pump or filter)? Of course, when it starts its hard to troubleshoot it.

Thoughts?

Post by **abscate** » 10 Sep 2016, 10:13

Best to get a can of starter fluid and see if it cures the no start, when it occurs. That will guide you to the fuel or ignition system as the problem

Diagnosing the components of fuel delivery like relay and pump are tougher, there you start with a fuel pressure measurement

Post by **sleddriver** » 12 Sep 2016, 19:26

No start cold or hot? You didn't specify. Also, what was the air temp the morning you easily started the cold motor? Might be the ETC. Could also be female end of the ETC connector is badly corroded, indicating an open ckt to the ECU, so it doesn't know how long the injectors should be open.

Been there, done both. New ECT sensor fixed the cold start problem in 50°F (no CEL). Several months later, CEL pops up indicating an intermittent ECT reading. The new sensor was still fine, however now the female end of the ECT wiring harness had to be rebuilt. That solved the problem to date.

Post by **scot850** » 13 Sep 2016, 10:26

It could also be a bad antenna ring or key chip. Try a different key if you have one and see if it makes a difference.

Neil.

volvooh · Post by **volvooh** » 13 Sep 2016, 11:33

Thanks all. Of course, I can't get the problem to replicate. I was looking at the no-start flow chart and decided to order a new fuel pump relay.

Sleddriver, to answer your question, it was a warm day- 80ish- but the engine was cold.

BTW- what is the ETC and where would I find it?

Post by **shiloh51933** » 13 Sep 2016, 11:51

volvooh wrote:Thanks all. Of course, I can't get the problem to replicate. I was looking at the no-start flow chart and decided to order a new fuel pump relay.

Sleddriver, to answer your question, it was a warm day- 80ish- but the engine was cold.

BTW- what is the ETC and where would I find it?

The ECT is the Engine Coolant Temperature sensor.

Have you got a reading on the fuel pressure yet? The fuel pressure reading can tell you a lot about what's going on with your car. Could be your fuel pump is on it's way out, maybe check valve or clogged fuel filter, ect..

Post by **shiloh51933** » 13 Sep 2016, 12:01

scot850 wrote:It could also be a bad antenna ring or key chip. Try a different key if you have one and see if it makes a difference.

Neil.

I believe if the immobilizer was activated by failing antenna ring or key chip it wouldn't allow the motor to crank at all, as a matter of fact it would do nothing. As stated he got it to crank over but he couldn't get it to start.

Post by **sleddriver** » 13 Sep 2016, 13:27

volvooh wrote:....BTW- what is the ETC and where would I find it?

Ooops....reversing my own abreviations now. Should have remained consistent with ECT...

volvooh · Post by **volvooh** » 13 Sep 2016, 14:56

It may not have been the proper equipment...but using a tire pressure gauge I turned the key to the on position an got a 20 psi reading and with the car was running, 50 psi at the fuel rail.

volvooh · Post by **volvooh** » 15 Sep 2016, 14:13

So I got the new fuel relay installed and started the Volvo up. Started it up and stopped it several times. I went out a little bit ago and it started, then abruptly stopped and would only crank. I was able to start it up a minute later.

I saw a thread another member posted with a similar issue. On of the posters suggested a bad fuel injector relay connection. The problem is, its not on top of the radiator in my car. Any one have any idea where it would be in a 1999 C70 Turbo?