230 GE rough idle & revving

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Ray230GE
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Hi, I bought a W460 230GE as a project, had it running, then the next day it was rough on tick over and sooting the plugs. I have noticed te air idle valve is pulsing open a bit and then closing any suggestions as to the cause? Thanks, Ray

Jdring
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Location: South of Oxford, UK. 87' 230GE SWB Manual, 89' 230GE SWB Auto, 2012 G350Bluetec LWB
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Re: 230 GE rough idle & revving

Searching the forum, there are a few previous similar issues with lumpy idle etc.  This thread looks useful:

http://gwoa.co.uk/forum/1991-230ge-lumpy-idle 

 

 

Ray230GE
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Re: 230 GE rough idle & revving

Hi Thanks for your reply, I have checked out the link, but it doesn't come to a conclusion. So further investigaton is required, looking at the wiring diagram the ECU controls the air idle valve so could it possibly be that?

 (The engine is an M102.)

Ray

prwales
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Re: 230 GE rough idle & revving

Air leaks can cause lumpiness at idle, or blocked or poorly functioning injectors, lots of things can including a dirty air mass plate

check these through on K-Jet websites

 https://www.tasteslikepetrol.net/2020/02/bosch-k-jetronic-basics/

Pistonhead
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Re: 230 GE rough idle & revving

Ray230GE wrote:

Hi, I bought a W460 230GE as a project, had it running, then the next day it was rough on tick over and sooting the plugs. I have noticed te air idle valve is pulsing open a bit and then closing any suggestions as to the cause? Thanks, Ray

Ideally this is a job for the garage or at least one who is equiped with an emmissions meter. First port of call is to check the emmissions, from your discription it suggests the engine is over rich hence the sooting spark plugs. I would not over look the basics. Check the spark plugs to see if they are correctly gapped and of the correct heat range.

The irractic idle can and most like sounds like false air leak in the induction system but would not equate to sooting plugs. You need to make sure there are no false air leaks initally then readjust the emmisiions. There were two engines specs employed in the 230 GEs', one with adjustable valves and one which was hydralic tappets. The distinction is looking at the rocker cover. The adjustable valve has a round dics sitting in between the rocker and the head hence the rocker has an arch in it where as the hydralic tappet rocker has no disc therefore a flat edge to it. Check and adjust as necessary  preferably on a cold engine.

There may be a issue to over riching due to a problem with the cold start valve if fitted or a cold start injector which has a blue head to the supply socket, disconnect that and see if the running improves. Does the engine run better when Hot? 

This is just a starter, could do with more info really.

 

Ray230GE
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Re: 230 GE rough idle & revving

The  K Jetronic article was good. After further investigation I can here the air idle valve opening and closing with the ignition on but without the engine running, the voltage on the two outer wires pulses and is hard to read, but would seem to be the cause of the valve pulsing hence my query regarding the ECU. The wiring diagram I have is from the owners handbook  and is limited. 

Thanks.