fritfly

Hi All,
New to this forum and hunting an issue down with my 2008 Pilot. Have had no luck whatsoever so need all your expertise

3 months ago the car began to shake at 20mph lose acceleration and judder at 20mph and 40mph, generally around gear changes.
Engine noise increased and gradually became louder in the rear cylinder rack.
Sometimes the CEL would start to flash and lose all acceleration alongside revs fixed in idle at 1,500rpm.
Error codes were talking about the VCM stuck on
I was advised the engine was shot and to replace.

I did so and 4 weeks afterwards we are back to the same issue. VCM stuck on, random misfires in all a cylinders, plus a couple of error codes relating to VCM sol and HO sensors.

We serviced the car 4 days ago and checked the oil yesterday and have found a lot of Aluminium inside. something is grinding but cant identify.
after replacing the engine i am at a loss as to what can be the problem it is back to exactly the same issue as before the replacement. We have changed plugs, engine, washed nozzles, checked oil sump for blockage, checked fuel pump etc.
Is it an electronic, sensor fault? what is the error VCM stuck on? I cant find any reference to this anywhere online.

Any help highly appreciated...

fritfly

gentle nudge on the above - from my reading there are issues with the O2 sensors and the cat but need to understand what else may be behind the fault...why cant i find any info online on "VCM stuck on"

Codes from diagnostic are below:
152-06 HO2 (AF SENSOR) B2 S1 HEATER CIRCUIT HIGH VOLTAGE
156 -16 HO2 (AF SENSOR) B2 S1 LABEL CIRCUIT HIGH VOLTAGE
21-08 VARIABLE CYLINDER MANAGEMENT SOL. V. CIRCUIT HIGH VOLTAGE
161-18 HOS2 B1 S2 CIRCUIT LOW VOLTAGE
114 - 06 VARIABLE CYLINDER MANAGEMENT SYS STUCK ON
166-01 CATALYST B2 EFFICIENCY BELOW THRESHOLD

also codes related to RANDOM MISFIRES IN ALL CYLINDERS

GoLowDrew

Sorry to read this. No idea on why all this is happening.

Wanderer.

Who advised this? What lead to this conclusion?

With all those sensor failure codes who knows. I would be looking at electronics or electrical though, not mechanical issues.

fritfly

yes looking at possibly replacing the ECU or working through the sensors somehow.But wouldnt the ECU just not function at all if it was shot?
Who advised it;-?
3 seperate mechanics. The fact that there was metal in the oil, the engine was making an exceedingly rough sound, one of the tappets at the rear had cracked alongside a hairline crack in the crankshaft seating.
Exactly the same issue then as now so clearly the mechanical engine isue is an outcome of something else. Im now trying to work out what that can be. I just cant find any reference to the VCM stuck on issue anywhere

Wanderer.

An PCM is a circuit board, there's lots of things that can go wrong on a circuit board and it will still "function". It's just computer programming reading voltages and adjusting other voltages according to the programming. If it is seeing X voltage input incorrectly it can adjust Y output according to code, even if that's not correct. Components fail prematurely occasionally, it happens.

It is easy to tell "yes this motor is shot, there's metal things where there aren't supposed to be" but they didn't bother asking "Why"? It's a Honda and it's 5 years old. That would raise a red flag to me that something else was awry besides the motor spontaneously failing. Did your old motor throw codes before it failed?

fritfly

yes the codes were similair; predominantly based around the VCM system.

Unfortunately I'm in a location (west africa) where mechanics are not the most well trained and conditions are not cohesive for proper testing etc. so you have to allow for some errors, but like you say a honda only 5 years old shouldnt be having these issues. unfortuntately it is. Having talked through with some logical tech minded people here we are going to test the o2 sensors and Cat, then try the ECU and other sensors. I suppose I was hoping someone had a magic wand on here that could tell me for definte what it would be.

Thanks for your assistance so far, its helpful!

EJ8VTEC

maybe find another 08 pilot and swap the ECU just to give it a try. I also agree that its an electrical problem causing mechanical problems.

HIGHLY HIGGGHHHLLYYY doubt it, but last time i had that many CELs on at once the problem was a bad ground at the alternator.

Acrdr

There was a bulletin regarding vcm on the 2wd pilots
The vcm system had to be replaced from the rear cylinder head

ricebike

sucked that it broke down mechanically...

so you repaired the engine mechanically, but is now hunting for the cause?

the only result i got from your key search words:

http://www.odyclub.com/forums/9-prob...vcm-stuck.html

click on the youtube link within that forum i linked

bm2bmw

Time to trade it in !