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

[abscate]

Definitely different on ME7

The car will always crank, with a key without a married chip it will start and tun for 1-2 seconds, then die. Subsequently, it will crank and not fire.

I don't know if it inhibits spark, fuel, both, or Oxford commas.

I have got both a cam sensor and ring antenna in my stash , can check part numbers tonight

[volvooh]

Just an update here.

I was able to get my hands on a denso cam sensor and antenna ring. The denso sensor was brand new. I installed it but no change. I got the key ring antenna from my son's '99 S70 (same MY as the C70) and still crank no start.

So it appears I have eliminated the Cam sensor and antenna. I was also able to attache a fuel pressure guage I am getting 52-54 psi while cranking.

Interestingly after I played with the antenna this afternoon (and it did not start), I came out an hour later and with a little cranking, started. Ran @ idle for about 10 min before it died again.

I appear to be getting a weak, intermidtant spark. If you crank it enough, it will try but will not catch and if it does only for a short while. Same with Starting fluid.

Should I order the Dice system to do a deeper check?

[abscate]

Okay , let's look at the 12 CDC on the coil packs. The wiring diagram is in a thread called coil wiring assignments , or close to that

[abscate]

It's terminal 4 on each coil. They should all be at battery voltage ( measure that) with key in Position II , engine off

They trace back up to relays that supply critical voltages. I found a lot of thermal damage in my Albany Volvofest thread and documented cleaning those there.

( search Albany Volvo Fest, it's down the thread a bit)

PS..I got your note on wiper switches, Evan paid me a box forward so I will do the same when I get to the stash today,

[rspi]

Sounds like it is loosing battery power, how are the cables?

[volvooh]

Abscate- I measured 12.2 volts at each coil prior to starting. It started and ran for 5 to 6 minutes. Rechecked and it was 11.8 volts after it died.

Rspi- Interestingly the battery was at 12.7 V this morning. I put it on the charger and raised it about 13.6 prior to starting. After it ran voltage steadily decreased to 13.0 before it died.

I'd like to run a voltage test directly from the alternator.

[volvooh]

More numbers. I was able to start it up again as usual a couple hours later. I got a reading directly off the back of the alternator. When the car stopped running I was getting 13.8 to 13.9 off of the alternator. Checked battery voltage after it quit running and I was at 12.2 v. Voltage off coils was 12.01 V with key in II postion.

Abscate- are the relays you are referring to the 4 silver ones in the fuse box?

[abscate]

Those are big voltage drops. It should be right at battery voltage and stay there. electronic stuff is not like points and condenser ignition systems , it likes good steady voltages.

There is a main power relay that feeds both the coils and injectors under the hood, I'll post a manual pic

[volvooh]

I had to take a break from this yesterday. Its driving me nuts.

So here is where I am at. I have swapped out a cam sensor, replaced and jumped the fuel relay. I have scanned with my OBDII and no codes. I have 55lbs of pressure at the rail. My voltage readings I posted last weekend were I believe in error. I check them myself three times and each I was getting a consistant high 13.5 to low 13.6 with the head lights on @ the battery. I am getting a consistant 13.7 to 13.8 at the alternator.

The car consistantly starts now when the engine is cool. BTW I want to view fuel pressure up to the point of failure to rule out a fuel pump heating up and cutting out. Would it you know it it started and idled for a good 10 minutes (kind of rough though) before a hose on my fuel guage ruptured. Until that point I was getting a consistant 53 to 55 lbs of pressure. Of course when I started it back up after the guage was removed it started for a just a few seconds and stallled.

I am thinking of swapping out the crank sensor and then the ECT maybe? I know a crank sensor should not kill the engine, but it appears the engine stalls as it is heating up and restarts after it cools down.

[volvooh]

I was also thinking about the MAF. I noticed when I was running it yesterday afternoon and disconnected the MAF it immediately killed the engine. Hooked it back up and it ran again. I also noticed by disconnected the MAF and spraying starting fluid in I got the car to fire. Reconnected and spray SF and nothing.

Could a failed MAF be my issue?