Deisel knock in a peugeot expert 1.9, what could cause this?

check oil level-condition -pressure===knocking is usually damage to lower end --rod knock --piston slap--failed bearings

That depends on the amount added and the engine, yours would be 7 parts diesel to 1 part gas. I do not have the different effects on engines using different ratios of deisel to gas, I suspect the richer the mix ratio of gas to deisel, the more noticable the reactions will be. First off there are two immediate impacts of diesel fuel mixed with gasoline: the octane is lowered and the fuel vaporization is reduced. The lowered octane may cause the engine to knock. Some engines have knock sensors and the electronic controls that will adjust the timing and other engine conditions to try to control the knock. If the knock remains significant it can damage the engine by causing metal fatigue eventually leading to failure of critical parts like pistons, connecting rods, heads. Some very old engines (e.g. 1950's tractors) can accomodate lower octane, but the ones found in recent autos are normally running close to the knock threashold. The reduced volotitility caused by the added diesel will cause hard starting and will probably result in some unburnt hydrocarbons remaining in the exhaust gas from the engine; these may be reacted in the catalytic convertor causing it to overheat. A modern electronic controlled emission system controls the oxygen level in the exhaust gas going to the convertor so the significant increase in hydrocarbons with controlled oxygen may save the convertor, but will likely result in unburnt hydrocarbons exiting the exhaust. This will result in a smell and air pollution. Gas will also damage deisel fuel pumps as well.

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Sounds like a rod bearing knock.

Based on what your saying the heads need rebuilt and you need new head gaskets.

Hi, if it's the engine pinging/knocking, you might resolve that by using higher octane fuel. A tune-up would be good too. Spark knock or preignition sometimes is caused by carbon build-up in the combustion chambers. Other knocking might be something physically bumping, like a loose exhaust pipe. A torn engine mount can allow parts to contact other parts and knock together as the drivetrain sags

This problem is caused by the injector which the wire for the rev counter pick up comes out of. Check your injectors then remove the one with the wire coming out of it clean and replace. If this doesn't sort both rev counter and knock get a replacement injector. I did this job a few months ago a little bit of stripping down is required but there were no real gotcha's apart from the injector needing to be put back in the head very tightly to prevent fuel leak. Hope this helps.

A sound like a old fishing boat is a Deisel,and your car isent a diesel IS IT
Iwould get it checked out at the local garage if I was you as it could be 1 of 6 things and i wouldent like to steer you up the wrong road when it could be something simple.
AND let me know please when you find out thank you [email protected]

if its at the top end its pistion slap
if its at the bottem end(of your engine) its a crank shaft bearing.

with out going into extream detail,

a ting sound at the top is a pistion slap.... replace all your pistions posibly over hual the engine.

a dubble knock that gose with rpm but sounds 2 knocks very every fireing of the pistion is a crank bearing..... replace your crank shaft bearings.... all of them b/c metal gose threw an engine extreamly fast and will destroy other beraings. this knock on start up will turn into a knock all the time, then a very louad knock that will end your engines life.

unfortunetly the answer is engine rebuild and fast.

I have seen this a couple of times but it usually comes on slowly with wear ov the servo, it might be honest but it does not sound it to me, maybe a second opinion would be good, even if the servo was inhibiting the fluid recouperating it would have been apparent to the fitter if they were good enough