Hi everyone,
This is my first question here. I'm quite practical but know nothing about cars, so bear with me...
I have 1998 VW Polo 1.0 with the AER engine and the Bosch-Motronic 9.0 engine management system (according to the Haynes manual, anyway). It's only done about 50K miles and is professionally serviced annually.
Whenever the car is started for the first time on a cold morning (under 5 degrees C or so), it starts first time and idles nicely at about 1000 rpm. But when I've pulled away, it loses power after a few seconds and the engine stalls. It won't restart straight away (just turns over nice and fast but never bursts into life), I have to leave it a couple of minutes before trying. After that, it's 100% fine for the rest of the day.
I was adviced to change the coolant temp sensor, which I did (genuine VW part of course, with blue ring) but that made no difference :-(
I also cleaned the distibutor cap contacts and rotor arm as they were filthy and pitted, but although the engine now ticks over more "evenly", it hasn't solved the stalling problem at all.
Any ideas out there? It's getting really annoying (I end up blocking the road nearly every morning now!).
Cheers,
Nick.
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Maybe you need new HT leads?
--
Espada III - well if you have a family and need a Lamborghini, what else do you drive?
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Thanks for that, but I changed them less than a year ago because one had corroded where it connects to the plug. Again, I used a genuine VW set. I checked them visually last week and they still look pristine.
Someone else suggested a fuel problem but I have no idea myself.
Cheers,
Nick.
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Nick
This sounds like it has been filled with the wrong grade [thickness] of oil. Too thick a grade can cause "tappet-jacking" of the hydraulic tappets until the engine warms up a little and it thins down.
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>>NickThis sounds like it has been filled with the wrong grade [thickness] of oil. Too thick a grade can cause "tappet-jacking" of the hydraulic tappets until the engine warms up a little and it thins down.
That's interesting, it did start just after its service in January, but then so did the cold weather.
The guy who serviced it is experienced and works in a Seat garage (+ so has serviced loads of Ibizas) so I hoped he'd use the right stuff.
Could you explain what Tappet-Jacking is, please?
Nick
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Nick
"Works in a Seat garage?" Moonlighting? So where did he get the oil - and what grade?
Tappet-jacking is getting very common - particularly on Zetecs, Ecotecs and small VW's. [This is the second - virtually identical - VW one I've answered in the last ten minutes.]
Hydraulic tappets are fed with pressurized oil, but have only a tiny exit port for bleeding air. If the oil is too thick when cold, the excess pressure can overcome the valve-springs' tension and the tappet's oil chamber then over-fills and holds the valves fractionally open, lowering compression. [The "fast turnover" symptom?]
Once cranked for a bit, the excess oil squeezes out and everything returns to normal as the engine warms and the oil thins. Try semi-synth 5W-30 if you're on 10,000 changes.
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Thanks, Screwloose.
I couldn't say what oil he used or where it came from, and don't like to ask...
If I changed it myself, is it an easy job? For example, would I need axle stands, or could I do it parked half on the pavement to get better access? And would all the old thick oil drain out by itself (assuming the engine was a bit warm), or is there a trick to getting it all out? I have the Haynes manual, which implies it's not difficult, and I am quite "practical" generally.
And would you recommend a particular brand?
Nick.
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Nick
Oil changing isn't particularly difficult and I'm sure the Haynes manual covers it comprehensively, along with the necessary safety precautions. You'll likely need a new sump-plug washer and something in which to drain/transport the old oil.
I've been a Valvoline distributor for the last twenty years - I used to stock around seven tons of 39 different grades: sadly, the new environmental regulations put a permanent stop to that too! Valvoline even pulled out of Britain; you have to ring Berensdrecht now.
Any top-quality 5W-30 semi-synth oil that genuinely claims to meet, or better, the VW502.00 spec [NOT GTX!!] will suffice.
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Cheers for that.
Do I need to change the filter too (seeing as it was allegedly changed last month but will be full of the thicker oil)?
Would a turn or two of PTFE plumbers' tape do instead of a new washer, or is that too botchy?
And just out of interest, why NOT GTX?
Thanks again,
Nick.
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Nick
The filter will be fine; the small amount left in there won't affect anything. Always use a new washer; changing a dripping one AFTER you've filled the sump is a bit messy! PTFE tape - no way.
My comments on the quality of GTX would doubtless upset our hosts; so I'll just paraphrase an very old Duckhams ad:
"If you want to know why you don't use GTX - just ask a man who knows about engines!"
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