Mac's Power

Don't know if this is the correct area to post this one in but I a friend of mine has a MY97 UK Spec car and it is running like a pig. ECU fault codes are 23 and 53. I know 23 is the MAF sensor but what's code 53?

Many thanks,

Paul.

pob on the job

Paul,
I dont know of any code 53 and have never seen one documented. Is it possibe you're mixing the 2 fault codes together? If so, 32 is the O2 sensor, and 35 is the Canister purge solenoid valve. Is the car showing the signs of complete MAF failure, ie will only tollerate light throttle and fuel cuts around 4K revs, with permanent check engine light?
I used to get it all the time but not any more

JIM THEO

According to "Subaru ECU codes" map there is no code 53, the last one is 51 (Neutral position switch is abnormal(AT only)).
JIM

Steve Lawson

Paul,

Code 53 relates to the Subaru immobiliser system,its a general code indicating the whole of the immo system.
Probably find the aerial round the ignition barrel has not picked up the code from the key at some point.
IMO nothing to worry about unless the car doesn't start.

Steve

Mac's Power

Ok Guys,

Many thanks for the help so far

Here's the full story. The car arrives at my garage last week badly spluttering but no sign of check engine light. I suspected the plugs as it was definately off a cylinder. I plugged in the Subaru Diagnostic Computer and got 2 fault codes 23 and 53. My manual only goes up to 50 but 23 is a common one......maf sensor.

I remove the maf to clean it and noticed a lot of oil contamination had happened. So I clean it and clean the boost control solenoid with was also clogged and all the necessary pipes. I then drained the oil and noticed that there was 6.5 litres in it!! I changed the plugs which were badly contaminated and refilled with the correct 4.5 litres of oil. When I restarted the car it sounded much better and wasn't off a cylinder any more.......but on driving the car it was still spluttering badly at 3,000 revs upwards. I did another diagnostic after clearing the old codes and was still getting 23 and 53..........so maf faulty was my opinion.

I replaced the maf sensor with a new one which I had in stock only to find the problem was still the same and the ecu code was still there. I then removed the new plugs again and they were Black. So it's definately overfueling.

Now anyone that has read this far......many thanks for your patience..........but thats where it stands. For once I'm at a loss......I dont think it's engine internals like valves or pistons as each cylinder holds good on a compression test with a reading of 150 on each.

Opinions greatly appreciated.

Paul.

pob on the job

Paul,
have you checked the continuity of the MAF sensor wiring?

If the maf sensor is showing fault the car will run very rich, hence the plugs, the O2 sensor will not switch either I believe in limp home mode..

FYI I have seen code 51 Inhibitor switch, immobiliser? And code 52 parking switch, a couple more to add to your list