Omega Owners Forum
Omega Help Area => Omega General Help => Topic started by: Rock on 05 November 2006, 19:39:56
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After taking some advice due to some throttle / idling problems, today I removed the throttle body and gave it a good clean with carb cleaner. It is now sparkling and looking like new!
I re-fitted the throttle body, and re-connected everything i had disconnected. (2 hoses on the throttle body with circlips, and the small one that slides on underneath) Plugged the FBW throttle lead back in.
The only other thing I removed was the bagpipes at the front but i have re-fitted that, plugging the 2 connectors back in, and the 2 thin hoses. Everything looked good, and as it was when I started. The problem I have now is as follows...
Start the car, and the throttle does seem more responsive. Revved it up to 6000 rpm and it sounded loads better. When taking my foot off the throttle, the engine settles down to idle, and after a short while the TC light comes on, and then when I press the throttle right to the floor it only gets as far as 2500 rpm.
If i then turn off the ignition and start the car again i get exactly the same thing happen. Have I plugged something in wrong or has some carb cleaner got in to the electrics part of the FBW throttle??
I have linked to a video I took displaying what happens.
Link to video (http://video.google.co.uk/videoplay?docid=6157053457673437323)
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Excellent video & audio. I don't have TC on mine but have the same erratic idle - but without the rev restriction - which is probably being held off by the ECU.
I'm sure one of the Experts will be along shortly to tell you which sensor is playing up & why.
Good luck.
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Thanks, I hope so. The car is unusable now as the same thing happens when in gear and driving.
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Thanks, I hope so. The car is unusable now as the same thing happens when in gear and driving.
Mine's a '95 & has three electrictal connectotrs, maybe the '01's different?
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Right, we need to know the TC fault codes which will require a tech2 or similar.......the TC on the later units has a CAN bus link into the ECU and this is putting the ECU into limp mode for some reason.....I suspect rpm signal fault or similar.....
Can you also measure the battery voltage when revving the engine, it shouldn't go much above 14V .......
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Thanks, I hope so. The car is unusable now as the same thing happens when in gear and driving.
Not sure what the prob is.....but im sure Mark can help :y....but what i can add is if gearbox is going into limp mode....use the shift to use 1st 2nd etc.....it works but a bit lumpy/snatchy :y
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Right, we need to know the TC fault codes which will require a tech2 or similar.......the TC on the later units has a CAN bus link into the ECU and this is putting the ECU into limp mode for some reason.....I suspect rpm signal fault or similar.....
Can you also measure the battery voltage when revving the engine, it shouldn't go much above 14V .......
I will go down to Vx in the morning and ask the service guy nicely to read the codes with his tech2. I don't own a multimeter so I will either get one in the morning or ask the nice Vx man to do it.
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at a guess ... throttle position sensor? Or don't FBW models have 'em?
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If you had bagpipes out, should be 3 electrical connectors:
Air intake temp, on 90 bend from air filter
MAF, just below it (the one we were pondering how it unclips earlier this week)
Front multiram (little way down, between the 2 bagpipes, near where vac hose goes on)
Also (though I know you haven't probably been near it), just check the connections to ABS unit, as TC is controlled primarily by ABS ECU...
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If you had bagpipes out, should be 3 electrical connectors:
Air intake temp, on 90 bend from air filter
MAF, just below it (the one we were pondering how it unclips earlier this week)
Front multiram (little way down, between the 2 bagpipes, near where vac hose goes on)
Also (though I know you haven't probably been near it), just check the connections to ABS unit, as TC is controlled primarily by ABS ECU...
Mine definitely has only 2 connectors. There is no connector on the 90 bend from the air filter.
The red circle shows the one we looked at on thursday, and the blue circle shows where the other one would be if i had it. (I think)
(http://img2043.photobox.co.uk/365565863c84f0d67dade6e380f8009afd012d9ba5b9d251c4263ef5076ae4cc9a622591.jpg)
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Never noticed that before...
Anyone know where air intake temp is on 2.6/3.2 then?
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The following is based on my experiences with other DBW engines. I've never touched a VX DBW.
Have you tried turning the ignition on without starting the car for 3-5 minutes? Also try re-connecting the throttle body. When you unplug DBW, the ECU has to go through an alignment process where it 'learns' the open and closed positions of the throttle plate. If not, then you end up in a drastic limp mode like you described. The TC button may be the cause as well, or maybe it is a symptom of the ECU limp mode.
Intake temp and MAF being completely unplugged should not cause the symptoms you are describing. The best thing is to read the trouble codes. Any OBD2 scanner would be a real help.
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Worth measuring battery voltage as said by Mark, in case overvoltage is knocking out something in ABS/TC ECU, causing it to tell engine ECU to reduce power.
Also, get that emissions bulb replaced (10 min job) and see if that is illuminated...
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Took the car down to Vx this morning and they have apparently spent some time diagnosing it. I am informed that bank 1 coil pack needs replacing.
When we read the codes with tech2 on thursday evening, it showed cylinder misfires on cylinders 2, 4 & 6. Would this fit in with them replacing the bank1 coil pack?
They also tested the voltage output from the alternator and said it was only 12.9V and that this might need replacing but that it was unlikely to be causing the erratic idling / limp mode problems.
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lol.....cylinders 2,4,6 are on bank 2........what cylinder(s) was the missfire recorded against.....
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When Jamie looked at it on Thursday, Tech2 showed cylinders 2, 4, and 6 having misfires.
I have just phoned my Vx garage and am waiting for a call back from the Service manager.
Were they right when they said the low output from the alternator wouldnt be causing the problem? Would it be wise to replace the alternator anyway?
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It wouldn't cause it.....if it was high it might....is it actualy miss firing then......it didn't sound like it was.
What was the stored TC code....
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It is mis-firing, but not all the time.
Will ask the service guy what the TC code is, if and when he calls back!
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On Thurs, defo codes for cyl 2,4,6 and multiple cylinders. No ABS/gbox/steering codes on thurs.
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On Thurs, defo codes for cyl 2,4,6 and multiple cylinders. No ABS/gbox/steering codes on thurs.
the guy at vauxhall says the codes he's got definitely points to bank 1. I explained the codes we got on thursday but he insists the problem is definitely with bank 1. He also said that the absence of a working EML bulb was causing the ecu to go into limp mode.
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On Thurs, defo codes for cyl 2,4,6 and multiple cylinders. No ABS/gbox/steering codes on thurs.
they also claim to have upgraded the software on my ecu. Is this even possible?
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On Thurs, defo codes for cyl 2,4,6 and multiple cylinders. No ABS/gbox/steering codes on thurs.
they also claim to have upgraded the software on my ecu. Is this even possible?
Yep, happens all the time. Isn't chipped, just newer factory software.
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Yes, the 2.6 has flashable engine ECU.
I would replace the bulb (10 min job), but doubt that would cause your problems...
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Lack of bulb will not cause limp mode......... >:(
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Vx still have my car and have fitted the new coil pack to bank 1 and surprise surprise its still behaving badly and misfiring etc.
They have now said that its because the nearside catalytic converter is blocked up that is causing the misfire...
Does this make sense to anyone?
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The amount of misfiring on passenger bank may have damaged the passenger cat, but until they cure the misfire that side, pointless changing it...
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They insist the blocked near side Cat is causing the misfiring, and not the other way round. I did ask them if it is the near side, why were they trying to replace the off side coil pack?
They have since said that tech2 is showing cylinder misfires on all 6 cylinders and that the nearside cat is the solution but possibly i might still need the off side coil pack as well, and possibly the nearside coil pack...
The bill so far for tech 2 diagnostics, time spent on car and them replacing the faulty bulb (without asking first) is just short of £200. AND THEY HAVEN'T FIXED ANYTHING!! (apart from the bulb!)
They now want me to spend £474 + VAT for the CAT and £36 + VAT labour (£599 inc VAT) plus then possibly another god knows how much on coil packs and they still don't know if this will resolve the problem!
If i replace everything they say might need replacing i'm looking at over £1000. :'(
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Willy nilly parts changing... :-?
I would refuse to pay for the drivers side coil pack......and get a passenger side coil pack.......
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I have already refused to pay for the drivers side coil pack. They insist the passenger side cat also needs replacing.
Is it worth me getting the near side coil pack and changing it myself?? Then seeing if the problem goes away? Or would he be right about me needing to replace the cat?
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Not a call I'd like to make... ...I would suggest that side coil pack may be suspect (or plug wells full of oil, or connector lose etc). Whether or not its knackered the cat I wouldn't like to say...
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Are the coil packs easy to replace?
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never done one, but cannot be that hard - move loom out of way, unbolt/unplug, replace....
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Ok, so i will get the car back from the 'worse than useless' Vx garage, and pay them for changing my bulb (without authorisation!)
I will buy a passenger side coil pack and fit myself and see if problem improves.