Question for the ETM and ME7 experts - RESOLVED Topic is solved

Post by **Twarr12000** » 06 Jun 2024, 22:07

I did a headgasket repair on the 99 S70 auction car and it runs great … for a while.

viewtopic.php?t=104303&start=10

It starts, idles and runs fine for about 2-4 miles then goes into what I assume is ‘limp mode’. Non responsive throttle and practically no acceleration. No ETM light and no DTCs. If I let it sit a few hours or overnight it runs great again for awhile.

I only have a cheap scanner for this car. The only anomaly I’ve seen is the ‘Absolute Throttle Position’. When the engine acts up the throttle position reads 0. The last time I drove it, I saw it was stuck at 39.6. degrees. (This could be an artifact from the cheap scanner). After restarting, it read 0.

I had replaced the ETM with a salvage yard unit when doing the head gasket repair because the original unit was obviously in bad shape from the leaking head gasket. I did the ‘8 second’ test on the replacement before I installed it and it passed. (Turn key to pos II, listen for buzzing and click).

Did I get another bad throttle module or, are the symptoms indicative of a different problem? Possibly a bad ECM? Wiring? Accelerator? I have yet another ETM but I’d like to be reasonably sure replacing it will be worthwhile. In all the documentation I’ve seen, there is no clear distinction between the “throttle position” and the “accelerator position”, which are 2 different components on these cars. I’m assuming the Actual Throttle Position reported by the scanner is the throttle angle in the ETM as reported by the ECM. Another curiosity is why there is no trouble code. If the ECM is going into alternate program 1,2 or 3, it should set the CEL, right? This further leads me to suspect a bad ECM.

Post by **Twarr12000** » 07 Jun 2024, 19:21

On further reflection, if the ECM is in alternate 2 or 3, it’s going to be commanding the throttle closed anyway. So, the problem could be any number of things. Without a DTC it’s back to basic troubleshooting.

Post by **abscate** » 08 Jun 2024, 03:50

Look for the late, 2012 on version on eBay. You want white label , made in Sweden or Italy. It’s still M/M but it’s non contact and will work for the rest of the cars life

Post by **Twarr12000** » 09 Jun 2024, 21:05

Update
I don’t know it’s the cause of the original drivability issue, but the car finally threw a code - P0014 “camshaft 2 over advanced”. I pulled the solenoid and it tests good. I reworked the connections to the new style solenoid.

I plan a trip to the area wrecking yard Thursday, I’m sure they’ll have a few. The yard has about 30-35 various models from 1998 to 2006. Anything else I should get while there? On my list, other than the usual plastic parts, are an accelerator module and ETM harness. I’ll look for the > 2012 white label ETM suggested by @abscate but I don’t recall seeing any in the last couple of trips.

Post by **Twarr12000** » 10 Jun 2024, 02:51

Both the intake and exhaust pulley mounting holes are slotted. Why? I noticed the exhaust pulley was rotated all the way ‘clockwise’. In other words the 3 mounting bolts were against the left side of the slots. I loosened them and centered the bolts - P0014 comes back immediately

Post by **Twarr12000** » 10 Jun 2024, 16:40

Checked the valve timing and it ‘appeared’ to be off 1 cog. (In reference to the crankshaft) Who knows? I originally used the Volvo locking tool with the crankshaft pin. With the cams locked and the crankshaft pinned, the marks on the camshafts do NOT line up. But both pulleys are slotted. I’ve read the mounting bolts are supposed to be centered. But this is a case of “choose 2 out of 3”. Are you supposed to use the slots to align the timing marks?? Maybe someone removed the exhaust cam CVVT hub and didn’t reinstall it correctly?

I’m almost ready to call the wrecking yard to come get this junk.

Post by **abscate** » 11 Jun 2024, 03:46

Search “understanding cam flank angle”
for a treatise in P0014. Basically, you aren’t putting the exhaust cam back incorrectly. It needs to be clocked hard counterclockwise and also set one tooth off per Volvo

jmartin919 · Post by **jmartin919** » 11 Jun 2024, 06:02

Did you do the "unload VVT" thing with the belt on?

Post by **Twarr12000** » 11 Jun 2024, 06:20

jmartin919 wrote: ↑11 Jun 2024, 06:02 Did you do the "unload VVT" thing with the belt on?

I turned 90 degrees past the marks and back.

Post by **Twarr12000** » 15 Jun 2024, 13:21

I set the valve timing using the vague instructions in VIDA for the 99 MY. (Turning the exhaust CVVT hub clockwise while installing the belt. Now all 3 timing marks line up correctly and the P0014 doesn’t return.

However, the car still goes into “limp mode”, or what appears to be limp mode, after a few minutes of driving. Neither the MIL nor the ETS light come on. When this happens the Actual Throttle Position goes to zero. If let the car sit a few hours it runs fine again for a couple of miles.

Now I’m looking at the accelerator pedal sensor. Is there a specific method to test this part? I’m hampered in regards to troubleshooting until I can locate a DICE or replacement. With the cheap scanner I have it’s unclear if “Actual Throttle Position” means the angle of the throttle plate as reported by the ETM or the position of the accelerator pedal. I would think if the ECU was commanding the throttle to some angle other than zero and the ETM is reporting zero, it would illuminate the ETS lamp and set a DTC.

Edit to add: Apparently the accelerator pedal sensor is a ‘bastard only’ part. All the Volvos in the wrecking yard have a different style. FCP has it for $309.99 (PN 30683511) but it’s back ordered with no ETA.