Gu td42ti Ute cold start engine rattle
Hi all its been quite awhile since I posted a thread on the forum but I have a problem I can't solve and I am hoping someone can offer some advice that will help me fix the issue I am having. I bought an 04 gu cab chassis with td42ti engine that has almost 300,000 kms on the odometer. I purchased it just before Xmas last year. When I first bought it and for several months after I had no concerns at all everything mechanically seemed as it should be, but as the temperature started to drop as we moved into the colder months an awful engine rattle developed when starting from cold first thing in the morning and what I find even stranger is that the noise is worse the lower the temperature is. The noise is horrendous, it sounds like it's about to throw a rod out of the side of the block or something that sounds just as awful (and costly) as that! The noise does disappear after the engine warms up and once it is warm the engine sounds like it should, the same as the other td42t engines in my other utes. It sounds like severe diesel knock almost. I took it to a guy I know who has a well known and respected auto workshop and he personally has had and still has alot to do with patrols. The engine was warm when I got there and he said it sounded beautiful idling over as it was, then I played him a couple of videos of the cold starts on different occasions and he said that it certainly didn't sound good but had no real opinion on what it could be. He did say he had heard another td42ti some years earlier with a very similar horrid noise but he was unsure what the guy who owned it did ( if anything ) to rectify the issue. He could remember the guys name and I tracked him down and asked if he managed to fix the problem, he said he had and in his words he told me that he had replaced the crank angle sensor and ever since it was quiet as a mouse. I thought awesome that's an easy fix so I thanked him and was on my way. After further research I discovered the td42 engines don't have a crank angle sensor they have a tachometer revolution sensor. So thinking that's what he must have meant I ordered a new one of these sensors. On the day I picked it up I had already driven the Ute so after I changed the part over the engine block had cooled down to about 15 degrees Celsius ( I have a temperature sensor on the block with a digital readout in the cab ) and I could have sworn that when I started it up after putting the new sensor on that it was in fact much quieter and I felt that way for the next couple of days on the first cold starts of those days as well. After a few days though the noise seemed to be just as horrendous and worrying as it had been before buying the new sensor. Maybe it was a kind of placebo effect I experienced with my mind telling me the guy said this fixed his problem so surely it will mine as well. Who knows, but it's still there and I would like to hear from anyone who has experienced something similar to this noise or can offer advice and or suggestions to resolve the problem. I would put up the videos of the cold starts so u could hear them yourselves but I am not sure how to go about doing that. Thanks in advance for any replies.
