'02 V70 - Mulitple CEL codes

[Mr. Detail]

Happy 4th of July to all!

Well, my P2 just limped home and made it to the driveway, so no towing today.
I want to preface this post with the fact I replaced the ECM (Re-man from Volvo) with a 1 yr. warranty and then that one failed and they replaced it for free. Also replaced the fuel pump last year that also had a 1 yr. warranty.

Just pulled these 4 codes:

P0328 = Stands for “Knock Sensor 1 Circuit High (Bank 1),” which means there's an abnormally high output voltage from the knock sensor. Some of the possible causes of the P0328 code include a defective knock sensor, a flooded knock sensor, and a defective exhaust gas recirculation (EGR) system.

P0527 = When the engine control module (PCM) cannot control the cooling fan as desired, it will set code P0527. A vehicle with this code should be taken into a repair shop for diagnosis.

P1026 = This error codes suggest a problem with the high-pressure fuel pump. This could be due to a faulty pump, a clogged fuel filter, or an issue with the fuel pressure regulator.

P2177 = This means that "the system is too lean off idle".

After seeing these four codes, can anyone possibly give me an advance plan as to what part(s) I can expect to replace? Thanks much!

[scot850]

Did all these codes appear at the same time? Seems strange that 4 potentially large failures all occurred at the same time, or have you had a check light on for some time?

First I would check the charging system and battery to make sure that you don't have low voltage to the system which can throw random codes and may put the engine into limp mode.

P0328 - Don't think your car has an EGR valve. I may be wrong. Has your PCV system been cleaned or relaced at any time recently? Have you tried the glove test to see if the crankcase is pressurizing?

P0527 - Is your car overheating? Is the needle on the temp gauge at a different point to normal?

P1028 - Would suggest a fuel pressure issue. Have that checked to see what fuel pressure you are getting. Have any of the parts listed been replaced at any time in the recent past?

P2177 - No idea. Too vague to guess at.

Neil.

[Mr. Detail]

Thanks, Neil for your response.

Yes, these codes all came up at the same time. The CEL has not been on at all for a long time.

I installed a brand-new battery about a year ago. Also installed a new alternator.

P0328 - I have not cleaned the PCV system at all lately. I have not done the glove test either.

P0527 - Did not check to see if the car is overheating because I barely got it home the other day.
Can't start it and run it until it gets to a normal running temperature, as it shakes too much.

P1028 - If you meant by replaced parts, the fuel pump was replaced over a year ago, also the ECM twice.
The battery is relatively new as I said.

[scot850]

Did a quick google and this may help understand P0328 - knock sensor:

https://www.ecufiles.com/obd-codes/p032 ... le-sensor/

There are a few generic YouTube diagnostic videos for this as well.

Pelican parts has a goo write up and diagnostic for Volvo 5 cylinders:

https://www.pelicanparts.com/techarticl ... cement.htm

Reading on the knock sensors failing, sounds like they could cause rough running if they fail. I always thought they were there to identify a rough running/pinking issue, not cause them!

There may well be a fueling issue, but the rough running you are mentioning and reduced performance and all these issues could be down to something as simple as a bad ground somewhere on the engine or a hose leak.

Neil.

[Mr. Detail]

Thx Neil!

[abscate]

Clear those codes and see what comes back. The knock sensors * never* go bad, there is other stuff going on.

[Mr. Detail]

Just a follow-up for anyone interested. My master mechanic just called and told me that it was my "throttle body" causing the CEL codes.
The good thing is there was a 2 year warranty on the most recent one that was previously replaced also under warranty. I just made it under the warranty. $685 for another throttle body if not under warranty.