moorsd123

I was under the impression that it was mainly new cams and valve springs? I think the early R400 Duratecs also had uprated big end bolts, but this was later stopped and standard ones used? The newer 420R's etc have the dry sump fitted too.

I'd check the TPS sensor (and wiring) or the Lamba sensor first? I had similar symptoms on my R400D, which turned out to be TPS.

I just shortened the wires and put new pins on, and strengthened them a bit using electrical tape. This will get me by for the time being, but I intend to make up a better connector like you have done (rather than buying the Caterham Upgrade). The standard wires are obviously a weak point and now they are slightly shorter will be under a bit more stress, so making a new loom will be a "winter" job!

Yeah thanks John, I saw the post come up and didn't realise it was from the original post you made...so replied with my experience (I've edited my response now so my comment makes more sense and to be helpful for anyone searching with the same issue in future). Looks like this is definitely a common failure point on R400D's...shame Caterham didn't use beefier wiring originally!! Thanks for your help again!

Had a closer look today in the daylight (after ordering a new TPS)...turns out you were right John, two wires going into the TPS connector were fractured. Quick go on the econoseal crimping tool (something that is proving to be of value since owning the R400D!!), and now all fixed. The temperature gauge also appears to be behaving, but think that is down to a dodgy earth somewhere, so will look into that further another day!

Found exactly this same issue on my R400D TPS wiring today...except two wires were broken!!. For anyone having this issue in future if you haven't already upgraded your coil pack loom to the upgraded "race" version, it might be worth checking this wiring too (particularly No1 cylinder)....early R400D's are prone to both this and the TPS wiring issue and both of mine failed within a matter of weeks apart! The newer wiring solutions are much thicker and are silicon coated to avoid the fracturing caused by high frequency vibration!

Another thing to consider if you want the over the ear type is if you wear glasses/sun glasses? Wearing glasses can reduce the advertised noise reduction level drastically, especially on cheaper models. The better quality ones aren't as bad as they often come with an option to fit gel ear cups which mold around the arms of the glasses better. Obviously may not be a problem, but worth consideration.

If I have the Aeroscreen on, I use some custom moulded ear plugs that I use for shooting, they block out the sound enough but still let some frequencies through so I still have a bit of situational awareness...they are very comfy as well. If I have passengers, or when I want to listen to music I use my JAL headset which is based on the Peltor Optime III, which are also very good. When looking at ear protection, you want to be looking at the advertised SNR number (which is the level of noise reduction), the higher the number, the more sound it blocks. 36SNR tends to be the highest but you may want to experiment on what suits best, as it's a balance between the level of protection and losing too much situational awareness.

Thanks John, I'd seen your previous posts about this (but not all the links work now), so looked at the TPS plug wiring but couldn't see anything obvious? Good news is that the panic is slightly over in that I have got the car started OK now and it's idling OK!...very strange? The temperature gauge is also working so need to take it out for a longer drive to get properly hot, as I wonder if that might be a factor in causing the symptoms I experienced on Monday?

Help!!.... Decided to take a closer look tonight and decided to spray some contact cleaner in the TPS, and around the various terminals in the engine bay (didn't disconnected any of the terminals other than the TPS). Went to start the engine and didn't want to fire at all! !! Went back to basics and checked there was a spark and fuel using No 4 Cylinder and there was...more attempts to start later and the engine fired but was really rough and possibly missing, and just stalls once off the accelerator pedal?...it also smells really rich? Bit stuck to be honest as not sure how the contact cleaner would have had such a dire effect given the engine was running OK (other than high idle previously)...or could it be the TPS is totally screwed now and the engine can't idle as a result??

Aluminium Plenum fitted. May be a coincidence that the high idle occurred at the same time as the temp gauge was playing up?

Hoping someone might be able to point me in the right direction with finding a fault?... Driving back from a track day yesterday I noticed that the car was idling at around 2000rpm but occasionally dropped to 1500rpm and was generally uneven, this was accompanied by the temperature gauge dropping to zero and again intermittently reading normal engine temp! The temperature guage basically looked like it wasn't working and then occasionally jumped back to life for a bit, then back to zero? Any ideas on best place to start and where to look, TPS?, Lambda?, wiring/poor earth? Car is a 2008 R400D

After a driver and passenger intercom set, similar to the Just Add Lightness ones (or equivalent). Will need to be the ear defender type and noise cancelling.

I bought the below crimping tool from Ebay. Glad I did as after trying a test crimp on my standard wire stripper/crimp tool it was pretty hit and miss. The dedicated crimping tool gives a much more consistent result!

Well, installed the upgraded loom this morning seems to be all working OK...actually think the car is more responsive, (could be psychological though). Only fiddly bit was getting the econoseal connector together properly so the pins would allow the locking plate to fit in the connector! Thanks for your input John, think I would have struggled without all the info you supplied!