95 x300 - cracked exhaust manifold and stuck CTS

X300
#1

Hi there fellow X300 owners. I’m hoping that one of you may be able to help with an issue I appear to have with my 95 4.0 sov. I’ve only owned her for around 4 months and am slowly rectifying someone else’s bodges, but seem to be having rich running issues. The two main questions I have are;

  1. had two cracked manifolds which I have repaired skimmed and refitted but will the continued rich running have buggered the origonal 02 sensors (both seem to have little voltage response and are normally around 0v.
  2. to mitigate the CTS as a culprit, bought a new one to swap it out but the old one is stuck and just spins (assume the sensor is spinning in the actual threaded portion?) Any ideas on how best to remove other than brute force…dont really want to have to remove the housing and drill it out!!
    Thanks in advance.
#2

Well done on rescuing these wonderful cars. Sadly cracked manifolds are very common on these cars, so don’t expect your repairs to last long term, but someone is making SS headers at a reasonable cost so all is not lost! Faulty 02 sensors will give rich running and you have diagnosed them as bad so swap them for new ones. By CTS do you mean the temperature sensor? This can defiantly cause rich mixture. There are 2 on the car. One that reports on the dash and one that reports to the ECU and it’s this second one that is the problem.

#3

Thanks for the info. Yes, it is indeed the Coolant sensor that supplies info to the ECU, and it is well and truly stuck in the housing, I fear ill need to drill it out! Would be interested to know who is making new headers for these as cant seem to find any other than pre used ones on ebay. Thanks again.

#4

Thats a bugger that its stuck…
Have a look here for headers Stainless Steel Exhaust Manifolds AJ16

#5

So as a follow up to no. 2 the stuck CTS sensor. I snapped the top plastic part off and grabbed the stub with some vice grips and it came out like a charm. Hopefully the uploaded photo may help others.

20210109_130123
20210109_1301232160×2880 1.3 MB

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