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"rough idle" - fixed? - ongoing problems?

Started by Firenze- · 14 Dec 2007 · 9 replies

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Firenze-Archived member
ok, for starters, id like to say thanks for your help with the rough idle stuff.... which was a while bak i doubt anyone that helped remembers but hey... anyways..... im reposting cos i wanna discuss some stuff. full story styles. ok.. i put a hks pod filter, everything was fine, then it started with a "it feels like im carrying a trailer" type feeling at above 80....., every now and again. Then the gear change to third, (its an auto sorry....) well i presume is third (80 kph +) started to get a bit.... lacking.... every now and again. Now also, every now again my car would...."start but, rev oddly" rough idle sorta thing, which would go away if i left it running turned it off tryed again. etc. took about 15 mintues to get over it. well now in the present about maybe 2 months after the reappearing and dissappearing power losses. for about 2 weeks, the clugging third (the best way i can describe how it is, is that i can push my foot about half way on the pedal, and there is no difference in whats going on, and it feels liek when someone puts a manual in too high a gear. then if i place it beyond half way, it goes into gunning mode [which i want to avoid]) was a permanent thing. my car then failed on me at work on last sunday. i was unable to get it started whatsoever. it took 2 hours till it would start. that night, i had to leave for a trip to creswick (30 mins from ballarat 1 and a half hour drive) now... at 110, which was the limit, the needle was shaky, and i freaked, never used to do that. we get to creswick in one piece. that night i had to drive out for two seconds. rough idle immediately. which made me tear. we left it and slept for the night. next morning had to drive into ballarat. i tried to start her, but she wouldnt, BUT i remembered what someone posted to me when i originally thought i had rough idle syndrome, to disconnect and reconnect the afm. i did it, and bang ho! off we go riding. i beleive that this was really asking for it from the car, as, on the way back from ballarat the car out of no where, un characteristically, did the rough idle bull**** at 80. now i kept my cool, and luckyly i was able to keep my foot on the pedal till the caravan park, scareily, i let go of the pedal to take a turn inside the caravan park ad my car shut off and just rolled. (you try brake and turn when the car isnt started, its ***ing impossible) thank god i was doing 10 k's. and you can imagine how scared i was to get this thing home at 110 kilometers an hour. we got home fine, thank god, shut the car off for a bit as i dropped off the misses and on the way bak to my place it clonked out. i restarted the car by disconnecting and reconnecting. now this was the only way i could seem to get the car to start. i booked an appointment with a mechanic that happened today, and he said he had no ****ing idea. i thought id take the punt and after the mechanics, i drove down to pick a part and pulled out a afm. (only 60 bucks with 30 day warranty) now, the mechanic said to me "pod filters are a pile of ****, its not worth ***ing around with the computer" which i beleive was a valid statement, a pod filter would be fine on a vl with a custom ecu, but stock, its not worth it, the 100 bucks you spend for what, .5kw? (ok joke its more, but you get the point) with a risk of ***ing up your car. well im saying that, cos i thought to myself id change over the pod filter seeing as im doing the afm, id rather it be more reliable than take risks (this is very debatable im sure, dont have any go's at me please) anyways!!! i changed the afm over with stock air box, and i been driving my car around all day at work, starting first time every time. the only problem is, i took it for a test run on the freeway, and the flat spot at 80 is still there, i can obviously get rid of it with the pwr button, but the fact that its so sluggy in that section just doesnt make sense. so the initial powerlosses i felt are still there. what are your opinions, do you think that my car will start with the rough idle again...? have i caused ongoing damage, i did have sysmptoms for 2 months, and my trip felt like it was asking for alot from the car??? or could it be that it is just TOTALLY unrelated and that my diff is ***ed or some ****. if anyone can shed some light... please im begging. even if you think that i just gotta give it a major service (im booked for the mechanic next week, fuel filter/oil filter/sparkies/trans&eng oil) if you think i there is ANYTHING i should tell my mechanic to do, please tell me, i havent got the facilities to do voltage tests myself unfortunately, basically i just want my car running normal, so that i can then go and chuck an exhaust on it ^^ hahahaha And i thought id tell my story, cos it ruined my holiday, and just a warning to everyone that is thinknig they're having the problem, fix it immediately, ive had such a head *** with the bull**** and by the looks of it its done some permenant damage. its a whole lot easier to fix it immediately then put it off. id hate to also think, that someone would die from something like this, i mean if someone else was dumb enough like myself to leave it for so long, and it clonked out on them at 80, god help you ***ing stop the car cos it wont, the brakes ***ing are impossible to push down and you cant steer. anyways. thanks for reading, all help is much appreciated, and i mean, thanks again, when my mechanic said that "i have no ****ing idea mate" (mind you the *** head tried to pull me in with 'oh i know my commodores mate, i used to work with brocky', ****ing suck my nuts) and you guys helped me and knew straight away, hench why im asking again. ust goes to show how good you all are, hehehehe thanks thanks thanks thanks
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Magnum06Archived member
Bit of badluck that you had to put up with it on a holiday. Cars can be ***ing stressful at times to the point where you just want to burn it or run it into a truck. Hope ya get it all sorted. You start with the basics first. Replace CAS, check AFM, check fault codes etc. Having trouble starting a VL often relates to the CAS.
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Firenze-Archived member
well i think ill make it a bit more clear. ive replaced the afm, and the car no longer SEEMS has a start up problem (who knows i might go out there today and it wont start, but i doubt it), THOUGH the loss of power 80+ is still there, maybe theres a loss of general power i cant tell, and the speedo is shaky at speeds above 95. so i should replace the crank angle sensor? can someone tell me what this looks like and where to find it so that i can go to pick a part hahahaha, and will i be able to replace it myself or should i get my dumb arse mechanic to do it? if theres any other ideas/help that anyone can think of, itd be much appreciated.
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NicheArchived member
Connectors on these cars are far more problem these days then sensors, often unplugging and plugging back in dozens of times will wipe off superficial corrosion from the wipes. The action of unplugging a 'bad' sensor and plugging in a 'good' one fixes things because its the connector not the sensor, hope you kept the old one. The loom connector is also subject to chlorine corrosion too which is released from inside the vinyl chloride insulation, so need to move and tease the wires now and then by bending them back just once or twice or better is give them a bit of a tug so it 'exercises' the crimp... Does sound like you have a CAS fault, in fact it seems you have more than one fault at same time that can be tricky but just eliminate one after the other, though if you have had the CAS more than say 6 years then might be worth replacing as the electronics inside gets heat and vibration stressed... CAS is the base of the distrubutor cap basically, the bit where the ECU wires go into the base of the distributor. I'll read through your novella again later and digest it after a break Some original photos have not been recovered yet.
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Firenze-Archived member
so for the moment i should be looking at replacing the cas. correct? do you mean the thing the cap sits on, the metal thing, i think thats what you mean. am i gonna be able to replace that myself? and play around with the wiring.... the car's done 270+ k's, so most likely the previous owner didnt change it, oddly though my afm has "tested in 2004" on it, so maybe the owner did change it aswell, but who knows (i got the car at 250 k's) should i be looking into getting an auto electrician to rewire ? Some original photos have not been recovered yet.
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NicheArchived member
All these things you can do yourself with a little preparation. Yes the CAS is the metal thing inline with the dizzy cap, theres a 4 pin plug into it, that carries the signal wires, 1deg pulse, 120deg pulse, +12v and ground. There should also be a ground spade connection that is separate. btw: Dont ever allow any spark leads to be anywhere near any signal leads, there needs to be at least 1 to 1.5 inches of air gap between spark leads and any CAS, CTS, AFM, TPS, Inejctor leads etc havent head my break yet - i'm random today
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Firenze-Archived member
your help is much appreciated..... i'll be sure to post back when im done, and for everyone out there, if i can do this ****, you can too hahahaha. ok... ill update when im done.....which is most likely in a week :S thanks!!! Some original photos have not been recovered yet.
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Firenze-Archived member
hey.... i went to the wreckers today..... and i pulled off the part that the distributor cap sits on.... like you said, and the guy said that that wasn't the crank angle senor and that the crank angle sensor was a disk or something with a magnetic ring where the main crank shaft is...... he said what i got was the distributor. also he said that if i wanted what i picked up, it'd be for missfiring/not starting, not for poor performance like im getting, which is what a bung CAS would cause.... please correct me on this. :Z
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NicheArchived member
The distributor cap sits on top of the crank angle sensor (CAS), if your car is a VL/VLT with the RB30 motor then your wrecker is a doooofooos. The CAS contains a disk with many slots in two arcs, the main arc provides a pulse for 1 deg timing resolution the secondary arc provides a pulse for the 120 deg cylinder identifier. The sensing is by infra red (optical) diodes and the disk is housed inside the bottom of the distributor. The electronics within the CAS gets subjected to high vibration and high temperatures, the failure modes under these conditions are many and varied and appear to have no consistency. If you have attended to everything else such as connectors, AFM, pumps etc then it is definitely worthwhile swapping out the CAS.
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BADVLSLArchived member
realting to your 80 flat spot, sounds like spark plugs man.. for the sake of $20 replace them..
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