Volkswagen Mark IV Forum banner
1 - 20 of 22 Posts

·
Registered
Joined
·
45 Posts
Discussion Starter · #1 ·
1.6 16v with the AZD engine in reflex silver, about 95k miles. Impulse buy because I needed a car quickly and know my way around Mk4s (or so I thought) and it wouldn't owe me anything if it suffered some sort of catastrophic failure. Going to log the journey here, mainly because the AZD engines are a bit different and it might help.

So, this is day one's report - the assessment and test drive:

Bad bits:

Missing centre vents - £15 to replace - DONE
Intermittent central locking NSR, and confused power window - BODGED - window locks switched on, door unlocks manually from the inside, just lock it with the button (button moves so the motor's running, I'll get round to having a look at some point. Door skin has been off recently because the handle trim is fitted poorly
Ticking from OSF wing area - turns out to be the PCV valve and completely normal (somehow I don't buy that, it's ridiculuously loud, and I don't remember my 130 PD doing it?
Ignition circuit fault - cylinder 4 - FIXED, new coil pack
Running lean - PENDING
Rusty bonnet - guessing going braless on the roads around here does that for a 20yo.
Only 1 key - quoted £125 for an additional one plus the SKC plus a repair of the fob on the existing one - PENDING
Slightly rough idle - put this down to the coil pack and got a discount for it from the seller

Good bits:

Everything else.
Doesn't stink, goes well, interior clean and tidy, stock stereo and CD changer works, manual climate control a big plus over Climatronic which I have a deep hatred for because of the legendary flap failure issues
 

·
Registered
2002 Golf S 1.6/16v BCB
Joined
·
72 Posts
Rough running will be the lean issue I suspect buddy, mine (2002 1.6/16v BCB) is also suffering a similar affliction...
 

·
Registered
Joined
·
45 Posts
Discussion Starter · #3 ·
Day 3:

Bollocks, suddenly cutting out after a long drive (1hr+) rolling into roundabouts/junctions. Restarts instantly and drives fine, no loss of power. Almost like the ECU isn't able to catch the idle as the engine speed drops off. Heel and toe reflex from trackdays a decade ago dusted off to compensate. Slightly hard starting too. Remedial actions as follows:

  • New coil pack for cylinder 4, based on VCDS fault - still stalling
  • Replaced air filter and checked intake - still stalling, but less frequently
  • Attempt to get VCDS scope running on it, only to find the crappy Marelli ECU isn't playing nice with my cable. Still on the search for a cable that works.
  • Do some reading and find that there's a thermistor-controlled flap in the airbox on the AZD that should close above 23C. It's there to stop the TB icing on cold starts and warm the engine up quicker. Looks like it's FUBAR on mine meaning the engine is getting dumped with hot air all the time, even when warmed up. Confirmed by checking inlet temps with Car Scanner Pro on Android with an ELM BT interface. Torque Pro used to be the king but this is awesome. Inlet temps in the low 60s even on a 15C day. Replacement airbox £25 on eBay, or I might bodge it closed permanently. Other option is to have one cover for summer and one for winter.
Car still performs well on short journeys, accelerates as per the quoted figures, and is doing adequate MPG even though when I bought it I stuck 95RON in it, had no idea it needed SUL! Still happy with it and enjoying learning stuff about it.
 

·
Registered
2002 Golf S 1.6/16v BCB
Joined
·
72 Posts
Temporary fix for the poor idle/cutting out at junctions etc, unplug the EGR valve buddy, then get the air leak fixed asap...

Ps, not just me then... 😬
 

·
Registered
Joined
·
45 Posts
Discussion Starter · #5 ·
Day 5:

Still running fine on short journeys and start wondering if the idle/stalling issue has gone away. Um, nope, does it again, once again just after an hour's driving. Really need to get VAGScope running on this to see if I can pin down what's going on but need to find a cable that works. Fuel trims seem off, but no EML or emissions light, and no lambda fault codes stored.

Decide to rag the hell out of it on a very hot afternoon blat around the lanes as I'm at the stage where if it chucks a piston through the head I won't mind. Still performing well, accelerating as it should, not using oil or water.

Then 5 miles from home and the red genie lamp of doom appears along with an oil pressure warning, engine workshop warning, and loud beeping. No smoke, no loss of power, no death rattle. Still think the worst and so nurse it home. Start reading up about oil pumps, sludge in pickups, and how to drop the sump. Check the oil level, no issue. Find out where the oil pressure switch is (top right of engine), check connector. Find it's a bit loose and that the plastic connector is wet with oil. Off to GSF in the missus' car to get a replacement just in case (£4.73). 24mm spanner needed to fit it, 5 minute job. Rag the car down the bypass, no oil light, seems to be sorted. Chuck 250ml of ATF in the crankcase, thinking it might just have been a bit of sludge, or buildup from having stood at the dealer for a while. I know the jury is out on the whole ATF thing but its worked on old cars for me in the past and I'm at the nothing to lose stage with this car.

Oddly, stationary rough idle seems better (yes, that makes no sense)

Am wondering if there's a TPS fault, although yet again no CEL or fault codes stored, because if I hold the revs at 1000rpm when stationary the idle hunts between 1100 and around 850. Another test for when I've got a VCDS cable that works.

Day 6

Starts first time. Idles perfect. 90 minute drive, mix of 60mph bypasses, country lanes at 30, and stop/start town driving. Idle stable throughout. No issue with stalling whatsoever. Parked on the drive though and there's quite heavy shaking and to me it looks like the tranny engine mount is, um, out of tolerance. Looks to be an easy/cheap job so that's next on the list.

Interior-wise I've deleted the armrest now because it gets in the way and inevitably the latch has broken. Fix the rear ashtray because, inevitably, the side trim had been knocked off. Looking for an ECS Tuning or genuine VAG cubby for the armrest hole, or potentially going for the legendary USDM centre (or should that be center) console.

Gets it's first tank of V-Power along with a dose of injector cleaner. £82 for a tank! More expensive to run than my Volvo 940 which does 25mpg on a good day!

Still loving it...
 

·
Registered
Joined
·
45 Posts
Discussion Starter · #6 ·
Temporary fix for the poor idle/cutting out at junctions etc, unplug the EGR valve buddy, then get the air leak fixed asap...

Ps, not just me then... 😬
EGR would already be unplugged if I had a working VCDS cable to do the adaptation. For the same reason I haven't had it and the TB off for a good clean yet. I'm guessing it's been run on 95RON for a while (common with these cars because people don't check, much like I didn't) and I bet it's sooty as hell in there.

If I fix this issue I'm going to be well chuffed as this is going to end up being cheap wheels to replace my missus' Mk1 Ka once I get the Volvo back on the road.
 

·
Registered
Joined
·
1,176 Posts
FWIW I had an issue where the car was struggling to 'catch' the revs as they fell to idle, it was resolved by using several tanks of vpower and a lot of ragging the car around (as much as you can with a little 1.6 anyway).

Replaced EGR + gaskets, vacuum lines, intake gasket, etc, but none of that made much of a difference at all.

It was worse during wet weather for me, the car would cut out. Whereas during dry weather the revs would just bounce a bit low then come back to normal idle.

Currently absolutely fine, rarely dips a tiny bit below normal idle, and I wouldn't even notice it had it not been running poorly before.
 

·
Registered
Joined
·
45 Posts
Discussion Starter · #8 ·
I've been doing an awful lot of WOT runs in mine which seems to have helped. Will see how it does today, I've got about three hours of local driving to do this afternoon.
 

·
Registered
Joined
·
45 Posts
Discussion Starter · #9 ·
Day 7

Ran perfectly for over 3 hours, no stumbling, no bouncing idle, no stalling, despite sitting in stop-start traffic for 15 minutes.
So I'm putting it down to the tank of VPower, new coil pack, and a dose of ATF. Will see how it goes when the hot(ter) weather reappears next week.

Now it's time to start thinking about upgrades. Interior first I think because the basic seats aren't the best. No lumbar adjustment, no front lip adjustment.
 

·
Registered
Joined
·
45 Posts
Discussion Starter · #10 ·
Still running fine, and now I've got VCDS working reliably I'll give the TB & EGR a good clean. Idle still occasionally a bit lumpy but no stumbling or stalling.
 

·
Registered
Joined
·
45 Posts
Discussion Starter · #13 ·
Well, on a hot and busy day on Saturday the stalling returned late in the evening. Unplugging the EGR for now and its definitely running much better. Idle rock solid and either it's making more noise or it feels more responsive. Will pop the EGR off next week when I've got some time off work and have a good look at it. Of course EGR disconnect triggers the engine warning light and Emmissions Workshop message but I can live with that (MOT isn't until next June)
 

·
Registered
Joined
·
45 Posts
Discussion Starter · #14 ·
One week on and EGR still disconnected. Idle still rock solid, absolutely no bouncing. Occasionally some very brief hesitations/stumbling, usually when the car has been sat at a constant speed with little throttle variation. Not had time to clean the EGR but will do that and I think I'll do the gearbox engine mount too as there's a lot of vibration from that side of the engine.
 

·
Registered
Joined
·
45 Posts
Discussion Starter · #15 ·
New key added - total cost around £50 (already own VCDS from my Passat & MK4 TDI days). Slightly nerve-wracking, particularly as I messed it up the first time by not adapting all keys at once.
I've seen a few posts about people having the immo light flashing even though they've got a key that starts the car. I think this might be down to a mismatch between the number of keys the car is expecting to be coded and the number of keys actually coded. Anyway, all good, and I can put my partly-broken fob in the kitchen drawer as a spare now.
 

·
Registered
Joined
·
45 Posts
Discussion Starter · #16 ·
A bit more fun with VCDS today - switched off the Service Now! message (as it has actually been serviced) and recoded the remote to unlock all doors at once. I get why VW do the double click unlock thing and preferred it when I was single but it's pointless and annoying when you've got a family to transport.
New, cheap, and probably dodgy EGR valve on the way to see if it fixed the stumbling issue. Not expecting it to but for £30 it's worth a punt. Currently got the old EGR plugged in - interestingly the Emissions Workshop and Check Engine light didn't go out until the third restart - possibly related to coolant temperature?
 

·
Registered
Joined
·
1,176 Posts
New, cheap, and probably dodgy EGR valve on the way to see if it fixed the stumbling issue. Not expecting it to but for £30 it's worth a punt. Currently got the old EGR plugged in - interestingly the Emissions Workshop and Check Engine light didn't go out until the third restart - possibly related to coolant temperature?
Normal to have to wait for the 3rd restart with a fault rectified for the light to clear, just in case the fault isn't actually rectified.
 

·
Registered
Joined
·
45 Posts
Discussion Starter · #18 ·
Well, that went well. Replacement EGR valve off eBay all fitted OK but impossible to adapt to the car in VCDS (known issue it would seem with cheapo valves). So beware, you need an OEM valve from Pierburg otherwise you can't do basic settings on it. P/N is 53389602 - but be aware, that PN is also an EGR valve for a Corsa which obvs won't fit. Going to track down a used one as brand new is around £120 and I'm not even sure it's the cause of the stumbling.
 

·
Registered
2002 Golf S 1.6/16v BCB
Joined
·
72 Posts
Why does it need adapting buddy, there's no computer/micro processors in it, or is there, surely it's just a basic stepper motor which does what the ECU tells it to ?...

The ECU either recognises it or it doesn't, no ?...

Throttle bodies work on the same process, there's no elastictrickery in them, no voodoo black magic, just a couple of cogs, a motor and a couple of contacts much like the ones found in a scalextric trigger...
 

·
Registered
Joined
·
45 Posts
Discussion Starter · #20 ·
Why does it need adapting buddy, there's no computer/micro processors in it, or is there, surely it's just a basic stepper motor which does what the ECU tells it to ?...

The ECU either recognises it or it doesn't, no ?...

Throttle bodies work on the same process, there's no elastictrickery in them, no voodoo black magic, just a couple of cogs, a motor and a couple of contacts much like the ones found in a scalextric trigger...
It's thrown a fault code - Basic settings incomplete, plus another one about the EGR potentiometer. If I plug the old one back in those codes clear, and I can run Basic Settings on it to set it up. Admittedly, it's not putting a warning light on so it's no issue for the MOT but no idea if it's operating correctly.
 
1 - 20 of 22 Posts
Top