Mondeo cranking but not starting.

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Posts: 1
Joined: Fri Feb 28, 2020 9:23 am

Mondeo cranking but not starting.

Post by RW-Cardiff »

Hi this is my first post and I am looking for ideas to help resolve my car problem or looking for somebody in the Cardiff area who has the equipment and knows how to use it to help diagnose a problem with my car.
The car is a 2009 Mk4 Mondeo 2.2TDCI which has decided not to start. I've been trying to sort it myself for some weeks without success. I've been running Forscan on it and there are no error codes so I am now looking for somebody that can do some more in depth diagnosis than just connecting a scanner looking for error code.
What I think need is somebody who can che ck the waveforms from the crank and cam sensors to determine if they are producing an output, I'm sure they are, and if so are they "clean" and are the crank and cam in sync.
I would also like to know if the injectors are being activated and if so are they flowing any fuel. I read a post on here recently from somebody with a Jaguar with a similar engine who finally diagnosed his problem as blocked injectors by comparing the injector signal with the fuel rail pressure using his scope and current clamp.
When the problem first started the engine would cough slightly for a couple of seconds as though it was trying to start but now it doesn't even do that.
So far I have tried replacing the crank and cam sensors and Forscan is showing RPM values hence my assumption the sensors are outputting something.
The cranking RPM is around 270-280, not sure what it should be but seems high enough.
A leak off test has not been done. Having seen dire warnings about the high pressures in the fuel system I'm reluctant to do much on that side and I haven't got the kit do to one anyway. And from what I've read it is supposed to be done with the engine running so not sure the results would be relevant. Maybe would be to somebody with more experience.
According to Forscan the fuel rail pressure is reaching the desired pressure but it does seem to take a few seconds before the pressure starts to rise, around 7 or 8 seconds. Seems too long to me but could be a delay in Forscan or the ELM interface I'm using.
Forscan is reporting the battery voltage dropping to 9.3 volts when cranking. A DVM across the battery terminals shows it dropping to 10.0 volts. 9.3V Seems a big drop. Is this low enough for the ECU to decide not to allow the engine to start? I have tried a new battery as I had my suspicions about the old one. Made no difference.
I've checked the compression pressures and all are around 325 PSI. Not sure what they are supposed to be for this engine. The Haynes manual I have doesn't cover the 2.2, only the 2.0 and quotes 400 PSI for that. I did find a suggestion on the internet that anything over 280 PSI was OK but don't know if that is true.
While I had the glow plugs out to do the compressions I found 3 were open circuit and one was high resistance so replaced all 4. As expected that made no difference.
As I also had to remove the fuel filter to check the compressions I fitted a new one. Took some bleeding. I checked the fuel pumped through while bleeding and found no metallic bits. I've since opened the old filter and again found no bits. So the fuel pump seems to be OK.
One thing I have noticed which could be very relevant is the oil warning light on the dash does not go out when cranking. I would expect it to. And it would seem very reasonable for the ECU to decide not to start the engine if it thinks the oil pressure is low or non existent. I don't know if the ECU does that or not.
Checked the oil pressure switch and seemed OK but replaced it. No difference. I have had the sump off and removed the oil pump and apart from some slight roughness at one spot it seemed OK but replaced it. With new filter and oil of course. Oil light still staying on.
So if there is no pressure and the pump is OK where is it going?
So any thoughts on what the problem might be or if anybody is, or can recommend anybody who is, in the Cardiff area that can run diagnostics that amount to more than just plugging a scanner in it would be very much appreciated.

Posts: 634
Joined: Thu Apr 24, 2014 8:32 pm

Re: Mondeo cranking but not starting.

Post by Technician »

RW Cardiff, don't be too quick to jump in and condemn the scanners. Live data is important but it seems you need to find somebody in your area that understands how to use and read a scanner.

Have a look for a professional in your area on here;

Posts: 160
Joined: Mon May 27, 2019 2:55 pm

Re: Mondeo cranking but not starting.

Post by Iver »

It seems R Cardiff has gone as far as he can and is actually asking for someone near him to take over and solve his problems. Surely some one here is close to him or can recommend someone ???

Posts: 1
Joined: Sun Jun 06, 2021 12:23 pm

Re: Mondeo cranking but not starting.

Post by GHolds »

Did you find a solution to your problem?

Posts: 7
Joined: Tue May 15, 2018 2:41 pm

Re: Mondeo cranking but not starting.

Post by HillVS »

We’re in Newport if you have access to recovery or a tow? Pm me if needed.

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