ECU fault codes 34 and 47

[jont]

Not sure if this should be in here or electrical.

Driving home from work, moderate acceleration in 4th. Turbo started to spool up, then suddenly the note gets much louder and higher. I back off immediately and notice the ECU warning light flashing. A couple of seconds later it stops. Drove home genlty and got codes 34 and 47 on the diagnostics.

Anyone got any ideas? The only mention of 47 is on rev 3 conversions. Car is bog standard rev 3 tubby as far as I know. It's also not mentioned on the diagnostics list. 34 implies abnormal turbo pressure/intercooler

Wasn't booting it hard, so I don't think it would have overboosted - probably was at about 3-3.5k?

Nothing obviously wrong like hoses fallen off - off to have a closer look now...

Thanks for any help,

Jon

[jont]

Right, been out for another drive to narrow down the symptoms.

1. Only seems to happen at full throttle/boost.
2. Nailing the car through 1st, 2nd, 3rd changing at high revs (6-7k) seems okay (only tried it once though)
3. Full throttle from ~2.5k in 3rd or 4th is okay up to about 3750, but then the jerks badly, really lacks power for ~0.5s (Amber ECU light comes on), it then clears and continues to pull for 1-2s, then jerks again (I backed off here as I don't want to braek anything). Changing up/back off and it clears and carries on driving okay on light throttle. ECU light goes off after a couple of seconds.

Any ideas? It's definitely turbo related (which is standard, standard re-circ BOV too), feels as though the turbo is stalling. Could a blocked intercooler cause this?

[stig]

Hi Jon, your symptoms sound to me like your hitting overboost, plus the error code 34 I am 99% certain is overboost too.

If its not anything playing up causing it, then maybe it was just a coolish night, it can happen sometimes.

You could try an ecu reset to clear the codes in case the 47 code is unrelated, it may help.
If then you get anymore problems then at least any error codes will be related to your current situation?


Theres some ecu error codes listed here on Bens site, (free plug lol) just scroll down about 1 page off that link.
http://www.btinternet.com/~netsurf/mr2t ... _ECU_Codes

[jont]

Hi Jon, your symptoms sound to me like your hitting overboost, plus the error code 34 I am 99% certain is overboost too.

If its not anything playing up causing it, then maybe it was just a coolish night, it can happen sometimes

You could try an ecu reset to clear the codes in case the 47 code is unrelated, it may help.
If then you get anymore problems then at least any error codes will be related to your current situation?


Theres some ecu error codes listed here on Bens site, (free plug lol) just scroll down about 1 page off that link.
http://www.btinternet.com/~netsurf/mr2t ... _ECU_Codes

Thanks for that - I've seen the error code pages, it's just 47 isn't listed on any of them.

I might try the ECU reset, although I've got the car going into 3S in a week or so for some other issues so I might end up adding this to the list...

<edit>Just found this very useful link: http://www.ayrpark.plus.com/errorcodes.html
so I'll add it in for future searches. 34 is indeed overboost, 47 is secondary throttle position sensor. Hmmmm....

[afennell]

Hi,

Searching the forum and found this, how did you fix this problem as i have the same codes.

[jont]

afennell - replied to your PM.

I ended up taking the car to 3S to have it diagnosed. Turned out the actuator was damaged, so failing to open the wastegate properly (if at all), so the car was indeed overboosting. New actuator (and had a decat fitted at the same time) and everything was okay again.

I think the 47 may have been unrelated - after it first happened, I cleared the ECU and took it out for another blat, and IIRC only got the 34 code back.

Jon

[Rogue]

I think the 47 may have been unrelated - after it first happened, I cleared the ECU and took it out for another blat, and IIRC only got the 34 code back.

Code 47 isn't listed in the BGB, although I've heard it quoted several times in conjunction with code 34 which is an overboost issue.

Patrick

[Caribbean_Blue]

I have had the exact same error codes come up before mate. 34 is excessive boost presure. As someone said overboost because it was cold yesterday night. Your ECU is doing its job in preventing turbo spooling to high which resulted in that 'jerk' cutting the boost and setting the car in 'safe mode' wont allow you to boost correctly.

What you will need to do it reset your ecu to clear the codes then your car will boost correctly again.

As for the code 47. This is a secondary throttle position sensor problem. I have this code all the time. My 2 is a Rev3 tubby non conversion. This error accured when I gunned it when it was very cold outside

I can't clear this code & have spoken to Matt @ Rogue about this as it isn't n their book. There are some tests on the throttle sensors that can be done just in case it is faulty. As for this code it is quite common, some say it could be to do with Traction control error even though I (maybe you) don't have TRC. To be honest I wouldn't worry too much about this error.

Reece

[afennell]

Thanks for the help,
Should I be getting error code 34 when I have a uni chip fitted?


I'm still having the same problem of the rev counter dying and the car sarting to mis.

This is starting to drive me crazy.

[Caribbean_Blue]

Thanks for the help,
Should I be getting error code 34 when I have a uni chip fitted?


I'm still having the same problem of the rev counter dying and the car sarting to mis.

This is starting to drive me crazy.

If its missing could be ignition component related & may be non-related to the other error, I may be wrong here though.

WHen was the last time the Dizzy cap, rotor arm, leads & spark plugs changed??

Also what are you using to control boost an electronic controller? Manual or just standard?

[afennell]

Car had a full service a few weeks ago. Dizzy arm etc all look new.

It's an intermitant fault, just dont understand why the rev counter dies at the same time. Might start changing over ignitor etc.

I'm using a uni chip with boost module. Can this just be unplugged?