G60 running rich

[bgilca 10]

Hy guys,

I just bought myself a g60 and the problem is that is running a bit rich, however i had good mpg(30 on highway doing 60-65mph) and i didn't saw any similar threads that have the same issues.

My problem is that it smokes when idle and a bit when running however, it's not the case to see the smoke in the mirrors, just my friends told me when following me. the smoke smells like gas and after replacing the spark plugs it started to be a bit better(holding idle straight away instead of loosing rpm and then bouncing back when pressing the clutch). the previous owner said that he replaced the blue temp sensor last month. also he said that the timing belt was replaced then(i was thinking maybe a +-1 tooth on the timing belt is causing it). also, i don't know if it's normal or not, the coolant stays at 80C(shouldn't it be 90C?). after driving it back home(around 2.5k km) i saw that the coolant level dropped a bit under the min, however i don't see any leaks and if they were visible i think that the car would lose the coolant more drastically.

 

what do you think?

[Gti_Jamo 10]

Typical G60 issues mate. I had a hell of a time sorting mine out. It's sounds like it's only running rich on idle. I'd check the fuction of the idle switch on the throttle body. Ignition timing also as if it's had a recent belt change and the auxiliary shaft has been incorrectly aligned then that will throw timing out as the distributor is run from that shaft. You may be able to compensate for that by hooking up a timing light and trying to set it up. If it is set up correctly via the shaft, the rotor arm (when cylinder 1 is at TDC) should line up central with a slot in the distributor housing.

 

Normal method is to highlight the 6 degrees before TDC mark on the flywheel with tippex. Have it up to temp until the fan has cut in, disconnect blue temp and rev engine 3 times above 3000rpm to engage service mode. Slacken 13mm bolt holding the distributor so it can be turned. (Mark it's original position just in case). Have someone hold revs at 2250rpm while you line up the 6 degrees before TDC with the pointer on the gearbox casing using a timing light connected to the ignition lead going to cylinder 1 ( revs will fluctuate as it's moved so whoever is controlling revs will need to compensate and have it remain at 2250rpm).Tighten distributor bolt, reconnect blue temp and rev 3 times above 3000rpm to come out of service mode.

 

If it is overfuelling on idle revving it will usually emit black smoke. Mine burned through 20 quid of fuel over two days just sat on the drive trying to sort but mine had loads of issues.

[bgilca 10]

Yeah, when reving it emits black smoke, also, if i'm not careful with the clutch when taking off, it would loose power for a moment, while the car behind me is covered in black smoke. And when i'm saying loss of power, i mean i cannot take off at all until it started reving(it's not reving for a few seconds although i got my pedal to the metal)

[Gti_Jamo 10]

My money would be in ignition timing since you mention the recent belt change.

 

Could be a dodgy oxygen sensor also. But only if the issue is related to temperatue. Like it is fine on initial start up but starts mis firing when it's gets past 50 degrees or so. The ecu doesn't consider the values from the sensor until it is warm and instead uses a base map for fuelling.

[bgilca 10]

Nope, it does it all the time, no matter what temperature. I'll check the ignition timing, also, would i be able to change the auxiliary shaft better than just to compensate it with the distributor? it's a hobby car so i'm keen to make things just right(no workarounds and whatsoever), i know it's a long way until i'll be able to drive it, but i'm ok with that.

[Gti_Jamo 10]

Yeah of course. It's always best set up correctly and the shaft being in it's correct position. There is not much adjustment at the dizzy due to it's wiring anyway.

 

Also, as I mentioned the idle switch, check the WOT switch (wide open throttle) as obviously if that is stuck closed it'll over fuel. Although more than likely all the time as oppose to just on idle. Worth checking them both with a multi meter anyway.

 

Once all that is done it'll probably be worth while getting the emmision checked and a basic tune up by a vw specialist as they are such temperamental animals when trying to achieve optimal performance.

[bgilca 10]

thanks for the help, i'll post here the results after i'm done. however, the car is currently being kept in another city so i wouldn't expect to be able to do much work on it in the following weeks.

[bgilca 10]

Hello guys, sorry for such a late response, i barely got time to take a look at the car in the past couple of months or so, so my current state is as follows:

Car still runs a bit rich however, much better than before. I tweaked the distribuitor( after o month of pain trying to get it unstuck) and it seems to be improved a bit, when cold there can be seen a bit of smoke however, when it warms up, it cannot be seen at idle, however, when revving the car it stil emmits quite a lot of it. I checked the blue temp sensor, isv, wot switch.

Any ideas on what can I do next?

[bgilca 10]

Hi guys,

 

Finally have sorted the car this week(it was the vacuum hose from the TB to the ECU) and now the car runs just fine(no smoke or mis-firing). However, it still developed some issues; it seems to run too lean now. when on wot, it barely accelerates, although it revs fine.

Also, when revving it while standing, the idle seems to be a bit dodgy, like, from 3k rpm drops normally to just under 1.5k , stays there for 2 seconds then drops further to 1k rpm for another 2 secs then drops to like 850 rpm.

 

At the moment, my money go on a dodgy O2 sensor. Ordered it already, waiting for my mechanic to replace it together with the spark plugs next week. hope it solves my issues.

If you think of anything else, I'm open to suggestions.

 

Thanks.

[PaudieG60 0]

Reset the idle on her after the o2 sensor is done

[16VG60 0]

Your G60 needs to have a full engine tune, to setup the basic settings for dynamic timing, exhaust CO%, and idle speed. This will establish a firm baseline and confirm the function of your oxygen sensor, ISV, and CO pot. So often this important process is overlooked on G60's and in as much so many are unnecessarily running out of trim. You will require key workshop tooling like a good quality engine timing light and a 3 gas analyser. You will also need to familiarise yourself with the procedure.

 

http://www.johnmitchellracing.co.uk

[bgilca 10]

Hi,

Thanks for the advice, the timing and idle will be done(by the mechanic, the only one in my area that knows the G60's... not so many options in Eastern Europe I guess) when the new O2 sensor is in, as for the ISV is buzzing when ignition ON, and if I crank the car over with it disconnected, it will idle rubbish and over fuel, so that one is working. The CO pot is set by multimeter at 520 Ohms, BTS was changed a few months ago with OE one from the dealer and a new Bosch induction coil. The timing belt and serpentine belt was replaced together with a freshly rebuilt charger in July, so I guess it's just the tune up that needs to be done now.

 

If you guys can think of anything useful, I'm open to it.

 

Thanks.