Advice on lumpy, erratic 2.0 16v - being a bit crap again..

[jonesyUK 0]

That will be my next port of call once I've replaced the Water Temperature Sensor. Where did you get yours from? Is ebay a good bet or am I likely to get something crap or from the wrong car. Can I use an ISV from an Audi for example?

 

e.g.

 

http://cgi.ebay.co.uk/VW-AUDI-VAG-DIGIF ... dZViewItem

[Jim 2]

Definately get the water temp sensor from VW..

 

As for the ISV, you can also get a used one from an Audi 80 16v as they used the same 9A engine. Thats what i'm running on mine and it works great.

[jonesyUK 0]

Well life is never easy is it. My local garage tried to get the "water temperature sensor" in from a number of local suppliers including VW and the wrong part was sent out by all of them. Turns out after much head scratching that the sensor I actually need was called a thermo timing switch. Well that's what it comes up as on VW's EKTA. But it came up on the Diagnostic's guys computer as a "water temperature sensor," when he scanned the ECU for errors. Its the sensor that goes into the side of the head, under the distributor cap and nearest the front ot the engine. A 2 pin plug connects to it. VW wanted £70 for a new one surprisingly so I'm getting one from a local dismantlers for £20. Hope this cures my kangarooing. Only way I can drive it at the moment so that it doesn't jolt my spine to death is to pull away in 3rd gear and and then drive in 5th under 2000rpm. Hope the new sensor cures this. FIngers crossed.

[jonesyUK 0]

Update: Well the "thermo timing switch" has been fitted but still no joy. Running better than before but revs still dropping constantly as I accelerate. More driveable than it was before anyway. I have found a split in the hose from the bottom of the ISV however. Tried gaffer taping this but made no difference at all. When hot, engine idle is still all over the place. Constantly reving up to 1500rpm then dropping to 500rpm repeatedly. Will replace this hose first, then think about getting another ISV from a dimantlers as this was recommended earlier.

 

There is also a grey, corrugated 2" air pipe going from the back of where the air filter is to the back of the engine, which has completely fallen apart. Could this have anything to do with my problems? (I doubt it to be honest)

 

I am beginning to run out of options now though. Local garage is going to fit a replacement ignition coil for me as soon as it turns up but I am beginning to get a little stumped to be honest. :(

[nocrap 0]

I know you said that it still didn't work after fitting the new thermo switch but just thought i'd say that if you want a brand new one i've got one that you could buy.........

[jonesyUK 0]

Will bare that in mind. Cheers fella. Is it a VW original or a GSF special? Will probably try all the other bits first, would be surprised to have 2 faulty thermo switches but you never know do you.

[nocrap 0]

Tis a bosch one....so VW

[Jim 2]

When the car is being lumpy and idling badly, do you get black smoke out of the exhaust? Re-reading your post, symptoms sound not unlike those of a dying lambda probe..

[jonesyUK 0]

I must admit, the oxygen sensor (I assume this is the same as the lamda probe) was my first thought. Especially as my CAT basically self imploded and blew through the middle box as well. Haven't noticed black exhaust colour but I will look at it tomorrow if I remember. I had discounted the lamda though as it didn't show up as being fulty on the diagnostic I had done but I'm not sure how reliable the diagnostic can be. I know they're not 100% fool proof.

[Yandards 0]

Got another line of thinking to add to this.

 

After spending the weekend changing the headgasket and valve stem oils seals on the MK II Golf I also spent a large amount of time getting the crud (about 2-5mm of it) off the ends of the valves and the tops of the pistons. Now I admit that some of the build up is due to the valve stem oil seals needing changing but having looked at various blocks/heads over the years this sort of build up is not uncommon.

 

This brings me onto my point, after starting the Golf up it was obvious the mixture was way off, I know the 1.8 16v cars and the G60s mixture can be adjusted but you need an exhaust gas analyser to do it, (just got a pro gunson one from Halfords £120 without trade card, £77 with it) so I can adjust the mixture on the Golf (and the G60 and the 16vG60 as well)

 

A sooty exhaust is a sign of of a poorly adjusted mixture and wear/gunk build up on the injectors, TB, spark plugs, pistons, valves, manifolds etc will change the original characteristics of the factory set mixture - even an air filter change will impact mixture settings.

[Toad 0]

Got another line of thinking to add to this.

 

After spending the weekend changing the headgasket and valve stem oils seals on the MK II Golf I also spent a large amount of time getting the crud (about 2-5mm of it) off the ends of the valves and the tops of the pistons. Now I admit that some of the build up is due to the valve stem oil seals needing changing but having looked at various blocks/heads over the years this sort of build up is not uncommon.

 

This brings me onto my point, after starting the Golf up it was obvious the mixture was way off, I know the 1.8 16v cars and the G60s mixture can be adjusted but you need an exhaust gas analyser to do it, (just got a pro gunson one from Halfords £120 without trade card, £77 with it) so I can adjust the mixture on the Golf (and the G60 and the 16vG60 as well)

 

A sooty exhaust is a sign of of a poorly adjusted mixture and wear/gunk build up on the injectors, TB, spark plugs, pistons, valves, manifolds etc will change the original characteristics of the factory set mixture - even an air filter change will impact mixture settings.

 

There's a guide written by Kev on here somewhere (got it bookmarked at home) for setting the KR up by ear which I've used to reasonable success in the past on my valver. Dunno about the 9a though??

[Yandards 0]

TBH Toadster there is getting it running ok by ear (and let's be honest here that's the way some people with a load of experience used to do it on carbed cars) or there is setting it up to run right according to a series of readings using diagnostic kit. It will also run better on diagnostic kit than by ear even on cars with a basic injection system such as K-jet as the tolerances are much tighter so you need more accurate kit.

 

Despite the extra sensors on the 9A block it is still basically a K-jet sytem and requires both the mixture to be set correctly and the balance plate that sits under the metering head to also be correctly set up. As such accurate mixture setting is vital due to a lack of adjustment available to the ECU when compared to a VR.

[Supercharged 2]

Going back to the last page a 2.0 16V doesn't have a thermo-time switch does it????

 

Jonesy - do you have the old part?? was the plug the same colour / what was the part number on it?

[nocrap 0]

Going back to the last page a 2.0 16V doesn't have a thermo-time switch does it????

 

Jonesy - do you have the old part?? was the plug the same colour / what was the part number on it?

 

Well i assume it does, as they've managed to change it.......must just be oddities like my one that doesn't, ETOS does say its for the KR and 9a

[davidwort 0]

Despite the extra sensors on the 9A block it is still basically a K-jet sytem and requires both the mixture to be set correctly and the balance plate that sits under the metering head to also be correctly set up. As such accurate mixture setting is vital due to a lack of adjustment available to the ECU when compared to a VR.

 

From what I recall if you disconnect both(?) elec connectors to the metering head the ecu will run in average settings, ignoring the signals from temp sensors etc, there was a 2.0 16v at Stealth like this at the last rolling road event which wouldn't idle or run properly, pulling the plugs made it run OK, and I believe it was the lambda sensor that was shot in the end they'd fitted a pattern part that was a pice of cr@p.

I'm sure the 1988-91 passat Haynes manual covers this.

[jonesyUK 0]

To be honest I just do not have the time to spend adjusting and fitting new parts. Getting married in 5 weeks time, kinda eats into your weekends :) I've done as many of the simple, easy things as I can but still it's running rough as anything. The 9A engine definitely has a termo timing switch as that's what it came up as on the EKTA (ETKA sp.) at my local VW garage and when I phoned up Stevens dismantlers in Great Leighs they knew exactly what I was talking about. Neither the thermo timing switch that came off or the 2nd hand one had a part no. etched on them though, so I can't tell you what part it is other than what it was sold to me as.

 

The upshot was that although the car runs better when cold, once warm its an absolute nitemare. Barely got home doing 25mph in 5th gear all the way last night. Have decided to book it into an independent VW specialists called Austins in Marks Tey over towards Colchester. They seem well thought of in lots of VW forums and a few hours of their time is gonna be far more valuable than a few hours at my local garage. Getting towed there for them to look at it a week today, so will let you know the verdict.

 

Fingers crossed the old girl will be back on the road soon. Sorry I've hijacked this thread a bit but there seems loads of people out there with 2.0 16Vs running rough so thought my experiences might help someone.

[Yandards 0]

Despite the extra sensors on the 9A block it is still basically a K-jet sytem and requires both the mixture to be set correctly and the balance plate that sits under the metering head to also be correctly set up. As such accurate mixture setting is vital due to a lack of adjustment available to the ECU when compared to a VR.

 

From what I recall if you disconnect both(?) elec connectors to the metering head the ecu will run in average settings, ignoring the signals from temp sensors etc, there was a 2.0 16v at Stealth like this at the last rolling road event which wouldn't idle or run properly, pulling the plugs made it run OK, and I believe it was the lambda sensor that was shot in the end they'd fitted a pattern part that was a pice of cr@p.

I'm sure the 1988-91 passat Haynes manual covers this.

 

Ah, thanks David 9A is not my strong point. Even so you would usually want those sensors working and as such a correct mixture adjustment is essential for best performance/economy.

[jonesyUK 0]

Back again. Latest verdict from the garage is that I appear to have ECU problems which is causing the mixture to be wrong. Engine is self correcting, hence the idle reving up then dropping back but it's apparantly running very lean. They've called in an electrical guy for this afternoon to have a look at it for me. I'm hoping its wiring or connector related rather than needing a new ECU but to be honest, anything at the moment would be better than the 1.0l Peugeot 107 hire car I'm driving about in!

[Thom 1]

I had a similar problem until recently, changed ISV and cleaned MAF, changed plugs etc. Turned out I had faulty wiring to the Throttle position sensor so sometimes it was all over the place, other times it was fine, just something to check out :)

[easypops 8]

check the 3 wires going into the switch for breakages, two of mine were broke but the plastic around them were intact ??? as soon as i fixed this....steady idle :D

that was two weeks ago and not a flicker, only took about 7 or 8 months to find.

keep going jim you will get there

 

seems the wiring for the throttle potentiometer might be more common than i first thought :?

[jonesyUK 0]

Just thought I'd update all things I have had to fix so far in the quest to try and cure the ropey runnning, coughing, spluttering and power drop off on my 2.0l 16V:

 

1. New CAT (Inside fell apart and debris kept blocking exhaust. Exhaust rattling, popping etc.)

2. New Lamda Probe.

3. New Thermo Timing Switch (White sensor, 2 pin, under distributor cap)

3. New Throttle Switch (Incidently, this was apparantly not set up correctly by my local garage. The VW specialists its at, at the moment have sorted this out. Not sure what was wrong though)

4. Cleaned MAF with Carb cleaner.

6. New ISV.

7. Replaced split hose to ISV (Apparantly this can quite frequently cause problems and is fairly common).

8. New Distributor cap.

 

Currently waiting on verdict on ECU. Fuel pressure regulator does not apppear to be doing its job properly. When it's triggered manually, ECU just packs up. Garage not sure whether ECU or pressure regulator are the problem at the moment, will find out next week. ECU is also still reporting a fault with the thermo timing switch / sensor even though I've replaced it. Again this is most likely to be a wiring issue or a problem with the ECU. More news next week

[jonesyUK 0]

There at last! Well after just over 3 weeks at Austins in Great Leighs they have finally worked out that I need a new distributor of all things. I was not helped by the fact that my local garage set up the throttle switch wrongly which was causing it to run even worse and Austins didn't work this out for a while. So you can add new distributor to the list above. What a mare. Hoping (touches all wooden objects within reach) that she runs OK for a while now. Picking her up on Monday, dread to think what the damage is but at least it's been cured. :multi:

[davidwort 0]

just out of interest, was it the hall sender in the distributor that caused the problem? they can give some odd symptoms when they start to break down, there's not much else in the distributor to go wrong really although the obvious one is the oil seal going and filling the thing with oil from the head.

[jonesyUK 0]

Not sure. Will ask tomorrow as I also need to ring the garage to find out where the random piece of rubber door / boot seal that was in the back of my car has come from. Bonus! Although got stung for just under 500 notes so I'm not feeling that generous about returning it. 4 hours of electricans wages was half of that as well. I hope his kids have a bloody good Christmas with my cash :lol:

 

ps. She drives like a dream and I have the biggest smile on my face at the moment. It's all been worth the 6 weeks with no car..... well maybe.

[Jim 2]

Bump. Stupid questions again here but i'm not happy with how my car is running atm. As it warms up during a drive to work in the morning it reaches a point where you hear an electric switch type 'click' and the car suddenly goes from idling at the correct rpm (around 800) up to nearly 1000RPM. I popped the bonnet the other day and unplugged the ISV with the engine running and nothing changed - revs didn't drop / falter or anything - should they have?

 

Things such as it being really lumpy when you first start it (like its misfiring) until you give it a little bit of light revving, and strange flat spots when putting your foot down at low revs - like you start to accelerate, and it starts to pull round the revs a bit, then bogs down and stutters for half a second or so then continues to pull fine. It's fine in the higher revs - always crap at the lower revs!

 

I really think I wanna book the car into Stealth for a setup (fuel mixture, etc) - it hasn't been running right for a while and only getting 140BHP at the RR day confirmed that (last time it was rollered it was at 157BHP - it has KR cams in it). Alternatively (looking at the comments at the top of this page) does anyone in the area know how to setup a 9A valver in exchange for beer / feeding, etc? :)