General again the cinq fails mot

[gregor]

hi folks been a while since iv done anything with my 1.2 cinq got all the mot repairs done last time and then went for another mot yesterday but it failed again on the back arches on the inside and the mot guy said it was in failed on that because the rust was 30cm within the area of the set belt mount and subframe, another point the car failed on is the lamda readings on emissions. The reading for the lamda was 1.3 and i think the guys said its meant to be 1.03 so my thoughts on that are it could be the the map sensor as the car dones idle slightly higher than they should be but i could be very wrong on the diagnosis any one got any thoughts on this.

cheers gregor

 

[rallycinq]

Sounds like an air leak to me.

Cheers

SPD

 

[fingers99]

Post the full results.

 

[spedo]

Hi Gregor
First check for air leaks as stated, if all ok you will need to do some detective work. I did a pre MOT check and my sun 1800 kept giving me a high HC reading which was puzzling, as I only rebuilt the engine only twelve months ago and everything was fine on the last MOT. I used a multi meter to check the lamda sensor and it was indicating rich lean as I would expect at its operating temp, my mind was thinking new cat, however the mileage was low so I did not want to condemn the cat at that point. I decided to test the EVAP purge valve which showed to be faulty; I replaced the valve which then had an immediate effect on the emissions and the idle speed also improved and subsequently the car sailed through the MOT. The purge valve is often overlooked but is vital for good emissions control and is situated beside the carbon canister. Make sure you check for a good connection at the plug and that the hoses are good and tight before suspecting it.
Good luck let us know how you get on.

 

[gregor]

offside seat belt anchorage prescribed are is excessively corroded.

nearside seat belt anchorage prescribed are is excessively corroded.

offside rear subframe mounting prescribed area is excessively corroded.

nearside rear subframe mounting prescribed area is excessively corroded

offside registration plate lamp insecure.

exhaust emissions lamda reading after second idle outside specified limits.

cheers gregor

 

[gregor]

the injector light is on too forgot to say and the car it like it hits its limiter at about 5000 revs.

cheers gregor

 

[spedo]

That changes things a little, you may be overfuelling, check the security of your wiring to the injector. Does the vevicle smell of petrol, if it does it may be ECT (engine coolant temp sensor) that is not reading the correct resistance back to the ECU.

 

[gregor]

where does that sensor sit is it jst the one on the radiator or what. i will check over the wiring loom tomorrow as that is when im planning to do most of the work like welding the new arches in the back (not looking forward to doing that) and doing the other stuff too. i cant really smell fuel but not really been looking for that symptom but will check for that tomorrow to.

cheers gregor

 

[spedo]

Hi Gregor
The ECT sensor sits on top of the thermostat (two wires blue connector), you can test it but it’s too much bother without a scope to read the wave form as they are only around ten quid to buy. Check the tail end of your exhaust for a strong smell of petrol as if you are over fuelling it will be thrown out the pipe. If you decide to change this sensor and things don’t improve get back to us.
Spedo

 

[gregor]

sorry another thing is the oil light is on constantly even though a just gave the car a sevice like new oil fiter, oil and the works but the oil light stays on only came on in the last few weeks around the time i serviced the car.

cheers gregor

 

[fingers99]

The oil light is critical.

You may be lucky and simply have knocked the wire off. Otherwise running an engine with low oil pressure for a few weeks is a sure way of destroying it.

The water temp sensor is on the inlet manifold, BTW.

 

[spedo]

It sounds like a wireing fault so you are right to first check out the loom for a short, as this is most likely causing the dash illumination and may or may not be the primary cause of the problem.

 

[gregor]

ok cheers guys i will get on it tomorrow, as tomorrow is my only day off then working an 8day week so i want to make tomorrow count so i will be all over it tomorrow.

cheers gregor