1999 C70 quit running while driving down the road ( recloned ECU) Topic is solved

[volvooh]

My C70 quite running today driving down the road, heading for a stop sign. It will not restart. I was able to move it to a safe location out of the way and will let it cool down to see if I can get it started. I don't think crank sensors will cause a car to fail while running, but will a cam sensor? Also, I have had an intermident crank no start that has been remedied by locking and unlocking the car, which I think points to a key sensor in the ingition? Would that cause the car to stall while riding down the road?

BTW, no codes yet, I will post back if I can get the obd read.

1999, 135,000

[cuhfs]

Fuel pump relay is an easy item to eliminate as a possible suspect. They too can be intermittently problematic.

[volvooh]

Thanks. I had an intermidant crank no start last summer (its only out May- Sept) and replaced the fuel relay. I've had a couple "no starts" that when I locked and unlocked the doors would allow it to start...maybe once a month (which is why I thought the ring around the key might be suspect). Today was the first day its stopped running while underway.

I went back 3 hours later and it started right up! It was nice to get it home but it just leaves me with questions. I'm thinking either cam sensor or the antenna ring around the key?

BTW- no codes.

Any thoughts?

[volvooh]

Will the Cam Sensor failing always throw a CEL? After restarting the car later in the evening, I did a scan with my OBDII and got no codes. I have used this reader for years and find it fairly reliable.

Cam sensors are $200 which is a very expensive guess. Any thoughts?

[JeffHicks]

My first thought is either fuel pump relay or fuel pump. But those are just wild guesses based on how random this was.

[abscate]

I don't think I have read if the immoboliser on your car, which is running ME7 software, only acts on startup or needs to be active during engine operation. That could be cleared up here, to be useful.

I don't think I would swap CAM sensors out yet. I could send you a used on to try - see part number in my PARTING OUT 1999 thread in PARTS

[volvooh]

Thanks- I might take you up on that. What I do not understand is why if a sensor is faulty I am not getting any CEL codes? Granted, I use a generic CEL code reader but its worked for me reliably for years. I suppose I can go to autozone and have them read it, assuming theirs is better than mine.

This is really maddening considering I am not just dealing with a crank, no start and getting stranded at the grocery store, I could be driving down the highway and boom...the car stalls and wont start.

[abscate]

YEah, thats why I think it is not that sensor. What about coil voltage - can you monitor the 12V to the coils and FIJ? Those are supposed to be on 12V all the time, and are fired by grounding by the ECU

Check the relays in this diagram...

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[scot850]

It is more likely a immobiliser issue I would suggest. Try cleaning the contacts on the antenna ring connector (the part around the ignition switch). Be careful as it is flimsy plastic and is only held in place by a flimsy clip at the side closest to the steering wheel. Cleaning the contacts is a 20 minute job. Remove the steering column cover (x3 x T25 Torx screws on the underside). Pull the steering wheel out as far as it goes and lower it to the lowest point but do not re-lock it with the lever. Carefully prize the cover at the front corners to un-clip it. Clips may break! Raise the upper part and flip it up against the speedo casing, and widen the lower section on the RH side to clear the ignition switch and pull the lower part down and off. The connection for the antenna ring is at the part closest to the speedo. Disconnect and clean with contact cleaner and a cotton bud gently and let dry. Sometimes just un-clipping and re-clipping the connector a couple of times is enough to remove any oxide build up on the contacts and then re-set the immobiliser with the key in the door lock and see what happens.

When we got the no-start situation with our 06 XC70 it was due to a bad transponder chip in the key. Do you have another key you can try? The 99 does not have a transponder but does have an ID chip in it. In fairness this is seldom the issue, it more more common for the antenna ring to be the issue.

When re-fitting the steering column halves. fit the lower part into position first and then make sure the upper part is fitted at the back at the speedo end first as there are a slide connection at that end and the front then should snap down into place. The 3 x Torx screws can be a little fiddly to align but once you get one in the other 2 are much easier.

Hope this helps and good luck!

Oh, the antenna ring is not too horrible from on-line sellers in terms of cost.

Neil.

[volvooh]

Update. I had the car out today. Drove 15 min to lunch and on my way back a minute into the trip, it died. Just as it had before, the engine cut out as I neared a stop sign. Luckily, I was near a business and was able to leave it in the parking lot.

It did give me time to run a few tests. First, no CEL. Second, I tested the pressure at the fuel rail with a tire pressure guage. I got 40 psi while cranking and about 5 to 10 at rest. I have a spare relay (I had a no start last year and installed a new one, but kept the original in the glove box), swapped and got the same readings.

I also disconnected the MAF, no change.

I locked and unlocked the car 5 times, no change.

I rowed the gearshift back and forth several sets of 30 times, no change.

I'm not sure 40 PSI is sufficient for fuel pressure at the rail, but assuming it is, I believe I am looking for something that is preventing a spark.

So I am thinking sensor or immobilizer? I don't think a crank sensor would kill the engine?

I am letting it sit a few hours and going to go back to see if I can get it to start, thats what happened last time.