IRRATIC START WHEN COLD
Posted: Sat May 04, 2019 3:08 pm
My 1991 Passat B3 has an RP engine but recently I put semi synthetic oil in by mistake. Since then my oil pressure warning and light comes on after about 20 miles. I decided to install a electrical oil pressure gauge which showed approx 80 psi on start up but as the engine warmed up the pressure dropped to almost zero.
I decided to drain the oil and check the oil pump and was surprised to see the filter on its suction pipe was vitually blocked with remnants of sealant used on the sump gasket. I cleaned the filter as well as any other remnants of the sealant in a hope that that was the problem. I replaced the sump and new gasket which had been showing oil seepage, as well as the rocker box cover gasket as that had also be showing oil seepage as well.
However on attempting to start the engine from cold it took about 10 seconds before it started to fire up, all be it hesitantly. Once the tick over was reasonable, I was able to drive normally and able to travel without problem although I haven't done a 20mile trip yet! Each time I start from cold the same thing happens but if I let the engine warm up and the stop for a few minutes, on the restart it fires up OK. I've checked spark plugs which appear OK , also the distributor and rotor arm were OK.
I'm not sure if this is an ignition problem or if it's a fault on the single point petrol fuel 'injector'. Any help would be appreciated.
I decided to drain the oil and check the oil pump and was surprised to see the filter on its suction pipe was vitually blocked with remnants of sealant used on the sump gasket. I cleaned the filter as well as any other remnants of the sealant in a hope that that was the problem. I replaced the sump and new gasket which had been showing oil seepage, as well as the rocker box cover gasket as that had also be showing oil seepage as well.
However on attempting to start the engine from cold it took about 10 seconds before it started to fire up, all be it hesitantly. Once the tick over was reasonable, I was able to drive normally and able to travel without problem although I haven't done a 20mile trip yet! Each time I start from cold the same thing happens but if I let the engine warm up and the stop for a few minutes, on the restart it fires up OK. I've checked spark plugs which appear OK , also the distributor and rotor arm were OK.
I'm not sure if this is an ignition problem or if it's a fault on the single point petrol fuel 'injector'. Any help would be appreciated.