GolfGTIforum.co.uk
Model specific boards => Golf mk3 => Topic started by: Stirring Moose on 21 January 2012, 21:46
-
Dear old 'Valver is up to tricks again. Current game is lumpy idling and bad/rough response to rapid throttle opening. Will run clean enough if throttle is opened slowly though. Had a good rummage around using Search and, as a result, have given the Idle Stabilisation Valve a good clean and lubricate and fixed a leaking vacuum pipe to the ECU. Seems to have improved things a little but not a complete fix. Am now in the process of changing the coil pack. During my Search, I came across numerous references to the infamous Relay 30, the ECU relay. Couldn't really get a clear picture of whether or not it might cause these problems though. Anyone got any thoughts on this?
S.M.
-
change the relay and see what happens,
use vagcom to see if it throws any codes up
-
Dear old 'Valver is up to tricks again. Current game is lumpy idling and bad/rough response to rapid throttle opening. Will run clean enough if throttle is opened slowly though. Had a good rummage around using Search and, as a result, have given the Idle Stabilisation Valve a good clean and lubricate and fixed a leaking vacuum pipe to the ECU. Seems to have improved things a little but not a complete fix. Am now in the process of changing the coil pack. During my Search, I came across numerous references to the infamous Relay 30, the ECU relay. Couldn't really get a clear picture of whether or not it might cause these problems though. Anyone got any thoughts on this?
S.M.
I had the exact same symptoms,was the first thing i changed relay 30,perfect afterwards :smiley:
-
Sounds like the hunt for relay 30 is on then! I'll let you know how it goes. Thanks guys.
S.M.
-
Ok, changed Relay 30. It wasn't Relay 30 :sad: Thanks for the suggestion anyway. Back to Search for me unless anyone can throw in any other bright ideas. To recap, she's now had: ISV clean, repaired ECU vacuum pipe, new coil pack, new Relay 30.
S.M.
-
I had a similar problem with my car and found a few faults along the way that might help you. Try and get it scanned if you haven't done so and check the status of the coolant temp sensor. These can muck about and cause all sorts of problems.
The wiring running around the back of the head to the throttle position sensor and idle switch can get toasty and melt as they sit over the exhaust manifold - check for broken wires there.
Crankshaft sensor wiring also tends to break up and this is visible allbeit with difficulty from under the car around the oil filter area. If theres a crack in the protection it might be worth it to check it further.
Leads - General cracking?
Earths - Under the battery tray especially
2x vacuum pipes - 1 from the inlet manifold to the PCV (square box with 2 breather pipes attached) 1 from inlet to the Fuel Pressure Regulator - If you changed the other one then these two might need changing as well depending on their condition. When you said you repaired the ECU vac pipe, did you change it? They can block up internally - this would normally cause a MAP fault to be stored though. Remove the pipe from the ECU and see if air can be passed through easily.
My fault was weird - caused by the alternator overcharging intermittently which in turn activates a overcharging protection circuit built into Relay 30 to protect the ECU. When it happened, the idle was rough, hard acceleration was especially rough, sometimes the fault didn't occur at all! Maybe worth seeing if you have a good steady 13-14 volts on idle with the fault present.
See what happens with that, hope it helps a bit
-
Hi, I had similar problems, everything pointed to Relay 30 and it worked for me.
This may sound stupid, but I did it even after being warned :embarassed: .... Did you get them mixed up and put the old relay back in instead of the new one?
-
@Leon 27: Wow! That's a fair old list to work through. We'll see if she responds to any of it but, either way, thanks for taking the time to put that lot together.
@Mellls: Luckily the old relay was black and the new one was white so chances of confusion minimal! One person who did seem confused was the VW parts guy. Asked for Relay 30 and he had no idea what it was. So asked for it as the Digifant Control Unit relay or somesuch and he was straight on it. Relay duly appeared... with a big black "30" stamped on it :rolleyes:
S.M.
-
My old valver went like this a while back, changed the usual relays, including the fuel pump relay, but didn't work.
Checked all the vac lines, breather tubes and the crank sensor, but in the end it turned out to be some faulty wiring, not round the back to the TB, but the part round the front where the injectors are. So have a look there when you exhaust all options.
-
Quick update. Haven't managed to do any more to the car yet BUT have managed to get the car undercover for a bit and put a blower heater under the engine to dry things out a bit. This seems to have improved things a bit - certainly not cured as yet but better. This is making me suspect wiring/connection probs so will probably tackle that next.
S.M.
-
Have you changed the dizzy cap? or checked it at least, might be damp?
I've got a similar problems with mine, which still haven't sorted :rolleyes:
If all goes well I might get a new VW coil, leads, dizzy, rotary arm, earth strap, exhaust manifold gasket and take the inlet manifold off and give it a damn good clean as its mining inside...
-
Inspect injection flange mount. Could be leaking and causing problems! I currently have the same problems of rough idling in drive but ok in neutral a hesitation engaging into first fear on an auto box. Car works normally once in gear. Pain in the neck trying to find the culprit. I feel your pain.
-
Ok, finally got into a bit of Golf twiddling tonight - last night was lost to the plight of a newly supercharged Jag that seems to suck harder than it blows and as for Wednesday just don't ask :angry:... but I digress! Have made a brief start on the list of wisdom you guys have kindly posted up here. Before starting I fired the car up briefly and she idled ok, I think just as a result of drying out a bit. Throttle response was still bad though.
First check was alternator charging voltage. Showed 14.5v which is a touch higher than I expected but it stayed rock steady up and down through the rev range so doubting that as a cause. Then did a load of connection checking, unpluging, cleaning and replugging the following: TPS, Idle Switch, Injector Loom, Crank Speed Sensor, Inlet Air Temp Sensor, Dizzy Hall Effect Sensor. Result is no change - fairish idle but stumbles if you jab the throttle.
Next step is to whip the battery and battery tray out and check the earths underneath. Just out of interest, what actually earths down there? Can find reference to them in the Hayne's book but only as numbers, not any description of what they do.
S.M.
-
hi
as mentioned before make sure you realy check the wiring that runs behind the inlet manifold well as the casing on the wiring breaks off and the wires short out on each other inside the trunking. mine done this and nuked my ecu when i rebuilt the engine last year lucky i had a spare.
-
Did as planned and went after the earth that lives under the battery tray. Looked pretty horrific on first sight but actually wasn't so bad when I got it apart. Cleaned all the connecters and reassembled them onto the earth stud with much copper grease. Put everything back together (complete with repainted battery tray - cheers Father!) and fired her up. She still stumbled initially but then cleared out and now, with a bit of running, is working well again. Can't really claim a total victory yet as it has only been one day but it's the best we've had so far!
S.M.
-
And it came to pass that, after nearly a week and a half of working perfectly, ye old problem did return. And Mr. Moose looked upon his 'Valver and was sore distressed! :angry:
Basically, the car has not been used for two or three days and now has started hesitating again. Only at irritation level rather than full on undrivability like it was but still not right. Seems like problems start whenever car is left for a while. My next plan is a good furtle in the dizzy cap - have got a replacement cap in stock so can try that. In the mean time, I have seen a number of mentions of the temperature sensor sending things a bit mental, but that if this fails it shows up on VAGCOM. So far mine always seems to scan ok. Is there any way this can go wrong without putting anything in the memory?
S.M.
-
Watching with interest as mine has similar problems when it feels like it
-
When the fault occurs see what the sensor is reading using measuring blocks on vag com. If you feel its implausible and does not match what is on the cluster its most probably faulty. The car wont see it as a fault if its still reading a signal but if the signal reading is -45 degrees or 180 degrees then that will have an effect. I've seen this on my old Mk3 where the reading wasn't moving, but disconnecting the sensor logged a fault.
Vag-Com is pretty useful when you are using the measuring blocks as you can see what the sensors are doing
Group Column 1 Column 2 Column 3 Column 4
001 Idle Speed Coolant Temp O² Sensor Adjust. For Basic
002 Idle Speed Engine Load Injection Timing Air Mass Injection
003 Idle Speed Air Mass Injection Throttle Angle Ignition Angle
004 Idle Speed ECM Voltage Coolant Temp Intake Air Temp
005 Idle Speed Engine Load Vehicle Speed Operating Condition
006 Idle Speed Engine Load Intake Air Temp High Correction Factor
010 Idle Speed Engine Load Throttle Angle Ignition Angle
014 Idle Speed Engine Load # of misfires Misfire Recognition
020 timing retard 1 timing retard 2 timing retard 3 timing retard 4
Interesting about how leaving the car for a while affects it, if that is the case then a new dizzy cap with a new arm could help and it will improve the spark so it is always beneficial. Someone earlier mentioned whether you replaced your dizzy, have you done your leads etc as well?
-
More very interesting info there, thanks for that. Unfortunately I don't have my own VAGCOM gear as yet so can't check this out straight away but will certainly see if I can sort something sometime. Other slight issue I have at the moment is that, having seen a bit of use in the last couple of days and thus got some heat through her, the car is back on song, really working well. Unfortunately I kind of know now that as soon as I leave her for a bit, she'll play up so still need to find a fix. Going to press ahead with dizzy work when I can. It's a pretty obvious one to tick off the list and I should've got on it sooner, both on the basis of what people have suggested and off my own bat, but I foolishly thought I'd nailed the problem with the earth cleaning. Silly boy! :embarassed:
S.M.
-
I had a similar sounding problem with my 8v when I first got it. It would hesitate at 3000rpm at the beginning (just noticably) but after a couple of months it was absolutely gutless above that figure and ran like a bag of turd.
After changing everything in the electrical circuit such as coil/leads/dizzy cap and rotor arm/plugs, fuel and ecu relays, the lambda sensor (twice) and the thermostat....it turned out to be the air flow meter.
-
I had a similar sounding problem with my 8v when I first got it. It would hesitate at 3000rpm at the beginning (just noticably) but after a couple of months it was absolutely gutless above that figure and ran like a bag of turd.
After changing everything in the electrical circuit such as coil/leads/dizzy cap and rotor arm/plugs, fuel and ecu relays, the lambda sensor (twice) and the thermostat....it turned out to be the air flow meter.
I must admit...I unplugged my air flow my air flow meter and the car didn't behave any differently which does point the finger at the flow meter...how much would a genuine air flow meter cost?
-
Mine did it too. Although it was actually quite violent jerking at 3k. Changed the MAF and all was good. I got a good used one for about £8 including delivery from the Bay. Expect to pay in excess of £100 plus your old unit in exchange if buying a new one from ECP/GSF.
-
The 8v engines have a MAF sensor however the 16v uses a MAP sensor which is built into the ECU. Both types of sensors basically calculate how much air is going into the engine that's why the fault symptoms will be the same when they go wrong.
S.M. maybe back to basics - with the car not used then showing the fault makes me think it could be something simple. But as you wait for Vag-Com try spraying WD40 or water displacement stuff on your electrical connectors - free and easy. Also check the condition of everything you haven't replaced, I had a non start fault with a coil pack that had a tiny crack in it causing water to get in. Would not start easily in the morning but for the rest of the day it would behave. Read that you changed your coil but check your leads and pull them off at either end to inspect the contacts.
Did you get to replace the dizzy arm and cap?
The earth cleaning wasn't in vain! Extra 10bhp for sure! And also its better you've cleaned them now rather than seeing them as bit of corroded dust in the future :smiley:
-
I had a similar sounding problem with my 8v when I first got it. It would hesitate at 3000rpm at the beginning (just noticably) but after a couple of months it was absolutely gutless above that figure and ran like a bag of turd.
After changing everything in the electrical circuit such as coil/leads/dizzy cap and rotor arm/plugs, fuel and ecu relays, the lambda sensor (twice) and the thermostat....it turned out to be the air flow meter.
I must admit...I unplugged my air flow my air flow meter and the car didn't behave any differently which does point the finger at the flow meter...how much would a genuine air flow meter cost?
Thats a bit weird though, it *should* revert to default settings if its unplugged and run normally (according to the guy who diagnosed mine - Mark Tweed at GT Motorsport in Stoke). That is what happened when we unplugged my faulty one. He came to this diagnosis after plugging it to a Launch diagnostics tool and then driving it and keeping an eye on the data received.
I got mine for literally £100 exchange at GSF - through my mates trade account. Genuine Hitatchi one. I wouldn't mess around with cheap ebay specials however, I know of 2 folks who have put cheap MAF's on cars for it not to cure the fault, and in the end it has turned out that the cheapy MAF was faulty and a genuine one has sorted it.
-
I had a similar sounding problem with my 8v when I first got it. It would hesitate at 3000rpm at the beginning (just noticably) but after a couple of months it was absolutely gutless above that figure and ran like a bag of turd.
After changing everything in the electrical circuit such as coil/leads/dizzy cap and rotor arm/plugs, fuel and ecu relays, the lambda sensor (twice) and the thermostat....it turned out to be the air flow meter.
I must admit...I unplugged my air flow my air flow meter and the car didn't behave any differently which does point the finger at the flow meter...how much would a genuine air flow meter cost?
Thats a bit weird though, it *should* revert to default settings if its unplugged and run normally (according to the guy who diagnosed mine - Mark Tweed at GT Motorsport in Stoke). That is what happened when we unplugged my faulty one. He came to this diagnosis after plugging it to a Launch diagnostics tool and then driving it and keeping an eye on the data received.
I got mine for literally £100 exchange at GSF - through my mates trade account. Genuine Hitatchi one. I wouldn't mess around with cheap ebay specials however, I know of 2 folks who have put cheap MAF's on cars for it not to cure the fault, and in the end it has turned out that the cheapy MAF was faulty and a genuine one has sorted it.
Yeah I can believe that
-
Ok, quick update. Haven't had chance to actually do any more to the car. Problem is still the same; leave her a few days and she drives like a pig, go to try the next day and she's fine. Just had her on VAG-COM and nothing showed up, either in the fault codes or in live monitoring, but then she is having an "on" day today and working fine so not entirely suprising! :angry: On the up side, have got the use of a data logger for a bit so going to see if we can catch the gremlin in the act with that.
S.M.
-
Sounds like a moisture problem spray wd40 into all the connections especially the main engine wiring plug (big black round should be on right hand side of the engine) I've also had a miss fire on mine when damp it was the ht leads earthing out on the coilpack it's worth a go and wd40 won't let the damp back in
-
Sounds like a moisture problem spray wd40 into all the connections especially the main engine wiring plug (big black round should be on right hand side of the engine) I've also had a miss fire on mine when damp it was the ht leads earthing out on the coilpack it's worth a go and wd40 won't let the damp back in
Worth a shot :smiley:
-
i tried all that as above because im having a misfire/lumpy running.
basically seems to happen more when wet although sometimes doesnt (like this morning it didnt, but tonight it did)
replaced the coil, relay 30, had new leads and spark plugs recently, and sprayed wd40 on the earths and dizzy to see if that changed didnt loads but is happening less i suppose.
seem if i put the throttle pedal down it will come back to life after loosing most power (although wont stall).. im beginning to think it could be then something to do with fueling/ going to check the fuel filter next weeek (as dont think thats been changed in ages!)
any other suggestions?
-
Gash - Did you replace relay 167 as well? Its the fuel pump relay, can drop out momentarily and cause a bit of starvation. Another thing I'd check is your vac line to the MAP sensor from the back of the inlet manifold, the fuel pressure reg vac line and there's a little one near the PCV.
-
didnt replace that one nope.
can you show me a photo of the va line ot the map sensor i know my way around the engine but unsure about that.
-
http://www.golfgtiforum.co.uk/index.php?topic=150754.msg1726760#msg1726760
Its the one marked blue and it should to to the ECU, it goes through the bulkhead. If its kinked, perished etc change it :)
-
Gash - Did you replace relay 167 as well? Its the fuel pump relay, can drop out momentarily and cause a bit of starvation. Another thing I'd check is your vac line to the MAP sensor from the back of the inlet manifold, the fuel pressure reg vac line and there's a little one near the PCV.
+1.
-
On the subject of fuel pumps, should you be able to hear them running every time you turn the ignition??
Sometimes I do, sometimes I don't, is that normal?? :undecided:
-
had a look and the pipe from the mani seems fine, doesnt seem to have a leak, il check saturday to see if it does anything by pulling it out when the engines running.
going to do the fuel filter too so will check if the fuel pump is ok.
with relay 167 is there a way to check if thats good? i know with 30 you can see if its hot after driving (mine does go warm)
-
I was having problems with car running rough when car was warm so changed plugs leads dizzy cap rotar arm cleaned all earths and throttle body checked all breathers replaced relays 30 and 167 and still had same problem and nothing showed up on vagcom either, I finally replaced ecu temp sensor and all runs sweet as now thank god