An Emerging Saga

[DJ]

Just serviced the 245 (B200F injection)- changed oil and filter, d/cap and rotor arm plus air filter.

First long fast run today and lambda warning light came on and the engine temperature gauge climbed alarmingly high. The temp was brought back down with the heater on full heat- round trip around 20 miles
I haven't had chance to investigate yet- but might I have disturbed something while tinkering (air mass meter is on the hose leading to the air cleaner unit, etc)?

Also, having removed the splashguard, I noticed a perished flexi aluminium pipe which runs from under the exhaust manifold (with a remaining 15" or so) and appears to have once gone (at full "pre-break-off" length) to a male coupling on the lower side of the air cleaner unit (near the bottom of the rad) I cut off a short piece of the remaining pipe in order to source a new one.

Am I correct in thinking that the routing is as above and what is its function (cold start, perhaps)?

Any ideas on the lambda and high temp. appreciated before I start jiggling around!

[Alec Dawe]

Yes, its a cold start air feed to the filter box.
No don't bother replacing it, can fry the filter air box if the thermostatic valve stops working. It does not seem to make any difference at all to the starting and running in this country. Its more like early 50's and before technology, where problems were to be had with carb icing. Seems to serve no useful purpose at all with the fuel injected engines, just a potential source of disaster.
Perceived wisdom on this forum is to discard the thing completely!

Did you do anything to the cooling system on the service. I believe that its possible to develop an air lock in the system, and the cure is to put the heater on to get rid of the air.

[tuning_redblock]

Hello DJ, you are indeed right about the cold start hose, it is not life or death if it is there or not, some people remove it and leave it off others replace with cone filters, you may be surprised at the cost of a new one from Hellfords etc.

Unfortunatly I don't kow much about the lambda sensor but I'm sure someone will

[DJ]

Many thanks to both swift reply posters- very useful.
I'm still dis-chuffed about the overheating, though- has the thermostat died coincidentally with the work I did (or a gauge/electrical thing) or was because I was ham-fisted and knocked something!

[Clifford Pope]

If the Lambda light is on it means there is a fault registered by the On Board Diagnostic unit. That is the small black box mounted on the top of the left hand inner wing, just in front of the windscreen wiper motor.
Haynes gives the procedure for reading it.

[DJ]

Many thanks, Clifford- I'll investigate asap.
Dave

[Glen Morangie]

You haven't said what year your car is - so a complete 'shot in the dark' - but might you have disconnected the knock sensor on the engine?

I think the ECU will advance the ignition timing until the knock sensor tells it to back off - and over advanced ignition would cause overheating.

Might also explain the 'check engine' light.

[DJ]

Many thanks, Glen Morangie. It's a '91 H reg. I suspected that I'd done something while servicing it as it would have been a b----y unlucky coincidence seeing as the trip when all went wrong was the first time I used the car after the service.
I haven't had chance to check the car yet as I'm still at work, but it's booked in at a main dealer's for checking on Friday morning. Where would I find the sensor?
Dave

[Glen Morangie]

Originally Posted by DJ

Where would I find the sensor?
Dave

I'm not absolutely sure on your car - mine's on the left side of the engine block, between the second and third cylinders.

As a general rule if I experience any electrical gremlins like this, I remove and replace any of the electrical connectors in the immediate area I have been working - often just disturbing them gives a bad connection, removing and replacing the connectors cleans up the contact.

[DJ]

Thanks again, Glen M,
I reconnected all the electrical connections around the engine plus the air mass meter connector on the air ducting; lambda light is now out and all seems to be working OK. I took a test drive to the local main dealer where it was booked in for them to investigate, and it behaved, and they were happy not to take my money (Lipscombe, Canterbury) so fingers crossed- end of saga!
Dave