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

[scot850]

Next issue could be the antenna ring which circles the ignition switch. These fail with age and either hard fail, but if you are lucky it may be oxidising of the connector on the back of the antenna ring. The antenna ring reads the chip on the key and if the read is lost due to a bad connection or antenna ring then it will shut the engine down. Not a horribly expensive part which you could try a used one from a junkyard also. Try cleaning the connector first.

One it is all clean, reset the immobiliser with the key in the door and then try again. However, I would have expected the car to through a communication or immobiliser code. That needs a Vida system to check it out I believe unless some of the high end readers are able to do so.

Neil.

[volvooh]

Thanks- How do I reset the immobilizer once it is cleaned, just by putting the key in?

[scot850]

No, do the door lock reset as before. I would disconnect the battery when checking the antenna ring as it has a constant live to it.

Antenna ring

05-15-2017 V70 NA repair pictures 011.JPG (2.61 MiB) Viewed 2473 times

Above is a picture of the antenna ring 'inside' (sorry don't have the outer face with the numbers on it). The clip closest to us is the flimsy part if you want to remove the whole unit to clean it. Carefully push it outward from the ignition barrel to release it and the front portion slides off first and the rear is hooked on but will come off once the front has moves outward.

The pin connector is in the black housing furthest from us in the picture facing away from us.

Good luck!

Neil.

[volvooh]

Well...after letting the C70 sit for a few hours, as I suspected it started right up. I got a 1/4 mi when it stalled again. Ended up towing it home.

Put it in the garage over night and wanted to pull it out and let it run to do some extra trouble shooting. I got 3 feet and it died. Just for kicks, I added a ground to the negative battery terminal and nothing. Still just cranks.

Pushed the schrader in at the fuel rail and got drips. Then I got a can of starting fluid, pulled the air intake and gave it a squirt, and it started right up for a few seconds. Looks like either a clog filter or failed fuel pump. Considering the track record over the last few months where locking and unlocking the car solves the no start problem, I not ruling out both and immobilizer and fuel delivery issue.

I am going to change the filter first since its cheap and easy and see from there. I have a feeling I am going to need to put a fuel pump in this weekend though, followed by service on the immobilizer connection.

[mrbrian200]

...after letting the C70 sit for a few hours, as I suspected it started right up. I got a 1/4 mi when it stalled again...

Considering the track record over the last few months where locking and unlocking the car solves the no start problem, I not ruling out both and immobilizer and fuel delivery issue.

Once in awhile you'll think you're really on to something and it's just a coincidence. I've been there. It won't hurt to check the antenna ring but this seems to me as a classic case of old age fuel pump failing. If you were able to perform a current draw test I bet you'd find that the pump is drawing more current than a new one would, and there's probably a more predictable correlation between problems occurring while driving on a near empty fuel tank on a warmer day than when full.

[volvooh]

Well...I appear to be back to the drawing board. Before commiting to a new fuel pump I decided to remove the relay and jump it. The pump came on immediately and I had 45lbs of pressure (via tire pressure guage) at the rail, both jumped and with the relay installed. Crank, no start. Then I sprayed starting fluid in the intake, again no start. I am going to try and check for a spark tonight as well as the immobilizer connection.

I feel like I am back to the drawing board...

[abscate]

Neil..

The antenna ring reads the chip on the key and if the read is lost due to a bad connection or antenna ring then it will shut the engine down.

is this known to be true? Not trying to be British, but thats something I would like to document.

Does anyone know if the immob shuts off the 12V to the coil (doubtful) or stops the ECU grounding of the ignition coils (much more likely) on the ME7 cars?

Might help troubleshooting.

OP - good job on DIAGNOSING the fuel system instead of guessing. There is no substitute.

[abscate]

Pushed the schrader in at the fuel rail and got drips. Then I got a can of starting fluid, pulled the air intake and gave it a squirt, and it started right up for a few seconds. Looks like either a clog filter or failed fuel pump. Considering the track record over the last few months where locking and unlocking the car solves the no start problem, I not ruling out both and immobilizer and fuel delivery issue.

Ohhh,, I let you down on this one. Remember that after some time (wish I could be more specific) the immobilizer goes into a mode where it lets the engine start, then die after a few seconds. After that first attempt, it won't fire at all. I documented this on ME7 one day when I had a boring telephone meeting.

I bet your starter fluid test was indeterminate and you are still stuck with an immobiliser problem.

Near end of this thread

viewtopic.php?f=1&t=81535&p=444597&hilit=V70T5M#p444597

[volvooh]

Thanks- I am stuck with something all right! I really thought I had id'd the problem with my starting fluid test, but I could not duplicate it. It does occasionally start and run- it did this morning with a variable idle for about 3 minutes and died.

I checked for spark yesterday. Except for one instance, I do not have a spark. Once (while grounding the plug to the engine) I got a weak spark and the car wanted to start, but then I lost spark again. Subsequent tests revealed no spark. I am going try and convince my son to do Neil's immobilzer ring connection cleaning today to at least rule it out.

I do have a '99 S70 that had a no start issue several years ago. If I recall, I was not getting any codes and my mechanic eventually replace the Cam Sensor and all was good. I still have the S70 but have been forbidden to swap sensors so I am going to need to get my hands on another.

[mrbrian200]

It is my understanding the immobilizer function verifies the transponder once when turning the key to the KPIII/crank position. If the transponder check fails it simply doesn't engage the starter. If it passes this check the starter engages/attempts to start the car. Once the engine is running it does not continuously check the transponder/kill a running engine. This functional behavior applies back through older Bosch management immobilizer systems such as a '99.

If you're confident that you've verified consistent fuel pressure and starting fluid didn't work the first thing I would suspect would be a combined no ECU spark command + no injector pulse (no fuel) scenario with failing cam and/or crank position sensors as the more likely culprit(s). 2nd thing would be intermittent fault within the ECU or wiring harness open/shorts.

On a '99 C70 I believe you also have the notorious Marelli electronic throttle module in play as well (closed-no air or open-too much air same as major intake leak).

Short of connecting Dice/Vida or at least a professional-level updateable/programmable OBD tool to the car with live data/shapshots/scope functions which can either read the OE specific DTC codes for, or at least perform functional diagnostics and display live data for the ETM and various sensors you're stabbing around in the dark.

Don't feel put out -- virtually ALL modern vehicles past around the early 2000's are designed around a level of complexity as a '99 Volvo and can throw even the most experienced techs with high end tools for a loop once in awhile. I consider us Volvo owners lucky- up to around MY2014-2015 we have the viable option...cracked Vida with a J2534 pass through device such as the most popular Chinese knockoff Dice units... which gives us a dealer level 'high end' diagnostic tool on the cheap. Though it only works with Volvos. It's a major reason I bought an '06 S60 and steered my sister into an '03 XC90. For around $100 and an old laptop can see things/diagnostics on these I would otherwise need to spend $1000+ on a professional level OBD tool or pay a well equipped shop or dealer to look at. Which I think is where you're at.
But even with a VIDA/Dice you still need a fairly high degree of knowledge to know what you're looking at and understand the intertwined relationships of various sensor readings/live data.