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[Boatboy]

At least I couldn't find it anywhere. Not sure it applies to DBW cars - do they have/need a separate TPS.

I've been suspicious of my rear multiram recently, mainly due to a flat spot mid range that clears big time c4k. Having searched the forum I found various references to giving it loads of revs to make it twitch - well maybe I am a bit timid but I got no joy through that route.

So, I started a process of elimination and quickly proved that the ram moves by hand, moves by direct vacuum and moves when the solenoid is connected direct to 12v, but was struggling to confirm the ecu was sending the right signals.

I started thinking about how does the ecu know that the engine status is 'full load - mid range'. The obvious one (no doubt more factors involved) is TPS value compared to rpm ie if the tps is indicating 'wide open' whilst the rpm is only managing 2k for example, the difference under normal running must be engine load.

Armed with this eureka moment I undid the two screws and slid the tps off the throttle shaft, still connected to the loom. I started the engine and gently rotated the tps's throttle shaft socket with a finger. Sure enough, even at idle, when the tps was 3/4 ish through its movement the rear multiram operated.

So now I've proved the multiram works, I now need to prove it works when it should. Any ideas?


Steve

[Jimbob]

cabled cars - very easy to test, just give it some beans
dbw - get someone to sit in the drivers seat and rev and you watch.

or some decent code readers will activate them on demand 

[Darth Loo-knee]

At least I couldn't find it anywhere. Not sure it applies to DBW cars - do they have/need a separate TPS.

I've been suspicious of my rear multiram recently, mainly due to a flat spot mid range that clears big time c4k. Having searched the forum I found various references to giving it loads of revs to make it twitch - well maybe I am a bit timid but I got no joy through that route.

So, I started a process of elimination and quickly proved that the ram moves by hand, moves by direct vacuum and moves when the solenoid is connected direct to 12v, but was struggling to confirm the ecu was sending the right signals.

I started thinking about how does the ecu know that the engine status is 'full load - mid range'. The obvious one (no doubt more factors involved) is TPS value compared to rpm ie if the tps is indicating 'wide open' whilst the rpm is only managing 2k for example, the difference under normal running must be engine load.

Armed with this eureka moment I undid the two screws and slid the tps off the throttle shaft, still connected to the loom. I started the engine and gently rotated the tps's throttle shaft socket with a finger. Sure enough, even at idle, when the tps was 3/4 ish through its movement the rear multiram operated.

So now I've proved the multiram works, I now need to prove it works when it should. Any ideas?


Steve

The Rear Multi Ram activates at around 1000rpm and when quickly blipping the throttle.
The Front Multi Ram activates at around 4000rpm so by revving the car quiet hard but nothing silly you should see it 

I have some pictures of both Multi Rams so you can find them somewhere, I will have a little look then post them up

[RobG]

At least I couldn't find it anywhere. Not sure it applies to DBW cars - do they have/need a separate TPS.

I've been suspicious of my rear multiram recently, mainly due to a flat spot mid range that clears big time c4k. Having searched the forum I found various references to giving it loads of revs to make it twitch - well maybe I am a bit timid but I got no joy through that route.

So, I started a process of elimination and quickly proved that the ram moves by hand, moves by direct vacuum and moves when the solenoid is connected direct to 12v, but was struggling to confirm the ecu was sending the right signals.

I started thinking about how does the ecu know that the engine status is 'full load - mid range'. The obvious one (no doubt more factors involved) is TPS value compared to rpm ie if the tps is indicating 'wide open' whilst the rpm is only managing 2k for example, the difference under normal running must be engine load.

Armed with this eureka moment I undid the two screws and slid the tps off the throttle shaft, still connected to the loom. I started the engine and gently rotated the tps's throttle shaft socket with a finger. Sure enough, even at idle, when the tps was 3/4 ish through its movement the rear multiram operated.

So now I've proved the multiram works, I now need to prove it works when it should. Any ideas?


Steve

The Rear Multi Ram activates at around 1000rpm and when quickly blipping the throttle.
The Front Multi Ram activates at around 4000rpm so by revving the car quiet hard but nothing silly you should see it 

I have some pictures of both Multi Rams so you can find them somewhere, I will have a little look then post them up

http://www.omegaowners.com/forum/YaBB.pl?num=1192573832

[Darth Loo-knee]

Ah, ones I took earlier 
Thanks Rob

[gsizoli]

We have the same issue, rear multiram doesn't work even if the rev is appropriate, however it works with direct 12V. It seems ECU doesn't control it. Vaacum is also OK. We will check the cable but no other idea...

[Boatboy]

Thanks for the replies but it's no wonder I'm confused 2 replies from well respected oofers, one saying give it some beans and the other saying a quick blip around 1000 rpm.  Am I missing something?

Whether I tried quick blips long bursts or beans a plenty, the only ram that operated was the front one, which is why I went the route I did.

I am now thinking the TPS pot may be at fault, not sending the right signal at the right time due to wear/old age. I'll do some resistance measurements in the morning.

Steve

[Darth Loo-knee]

The rear multi ram activates at 1000rpm ish and when you give quick blips of the throttle... try it and see.

The front multi ram activates and around 4000rpm.

If the front works but not the rear you could always try swapping the front solenoid to the rear, see if the rear works then 

[Jimbob]

Daz is more correct.....


I give equal beans to test, as you pass the low revs one on the high revs, and I can never remember which way round it is, so I rev from nowt to quite high to check both, looking at each in turn 

[Boatboy]

Jimbob - thanks for the clarification
Daz - they both work mate, just that the rear is not being triggered for some reason.

Just need to get the slow cooker going and I'll be out to test that TPS. Man of many talents me

Steve