E46 Camshaft Sensors and lower intake boot


Zorg Guru (V)
British Zeds
Nov 25, 2012
Newport, South Wales,UK
Model of Z
Z3 M43 1.8 (1999) and Z4 E85 2.5 (2003)
Not on a Z but on my mates 2.5 Series 3 Coupe from 2001. Lumpy running juddering at low speed, bad tickover.
Code reader on it revealed codes set for camshaft sensors inlet and exhaust. Car did not have a MIL light on.
Replaced both camshaft sensors, also spotted that the lower intake hose had a hole in it where the small tube that feeds the idle control valve branches off the main boot. Replaced after stripping down the pollen filter housing and removing the airbox and the small plastic panel at the left side (passenger side RHD car) of the rear of the engine compartment. Disa valve also had to come out to make room to get to and see the worm drive clips holding the lower boot to the intake and idle control valve. These clips are a nightmare to get to, I managed using a flexible 6mm socket driver made for tackling worm drive clips that I bought years ago when fitting stainless hose clips to a Morgan I had. I had to lube the boot to get it to slip over the intake stubs and get the bellows into the right orientation, there is a rubber flap on the end of the hose that fits agains a raised position marker at the bottom of the intake stub, the flap has to be against this raised marker to get it in the correct place so the upper boot and its joining ring are fitted at the right angle in order to fit onto the Maf and airbox. Bit of a nightmare getting it all in the right place and doing the clips up, without the flexible driver it would be even harder to button everything back together. Access is probably just the same on Z's fitted with this E46 engine.
Glad to say car was tested after all codes had been erased and given a test drive, driver reported power restored and idle back to normal. Codes checked and none had returned.
The Camshaft sensors we fitted were from Carparts4less on the web and were manufactured by HASS, these worked straight out of the box and seemed just as good as oem part they replaced, they come with new O rings.
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