Lambda Sensors.

[paulathome]

Coming to work this morning, the engine started to run rough, very rough.
It appears to have shut down the left bank of cylinders as when I got to work the manifold on the near side was only warm and the offside hot.
Could this be a Lambda sensor fault as its seems to be getting fuel by the stick of petrol but not running.
Had this problem for a week or two, but only after a run and then stopping for ten minuits.
On resart in then seems to be running on one bank only. Its been fine when starting from cold however
until today.
Any ideas guys?
Fitted new coil, ECU temp sensor, rotor arm, dizzy cap, recent HT leads.
The only thing common to each bank are injectors and lambda sensors.
Cheers
Paul.

[poorpeet]

Could be. I'd try checking & cleaning the connectors first. They are the big white ones. One of mine was very green! Next, if you have the right type of tool, swap them over & see if the fault transfers.
Good luck

[blitzracing]

The engine will still run on both banks even with a lambda disconnected. The ECU simply runs the fuel map without correction for that bank, you'd hardly notice, unless the ECU light comes on or you have a fault code reader. Even if the lambda voltage was stuck low all the time, the ECU will not try to compensate untill it sees a rising lambda voltage, so again simply no compensation. I doubt this area is causing the fault.

[That Daddy]

blitzracing said:

The engine will still run on both banks even with a lambda disconnected. The ECU simply runs the fuel map without correction for that bank, you'd hardly notice, unless the ECU light comes on or you have a fault code reader. Even if the lambda voltage was stuck low all the time, the ECU will not try to compensate untill it sees a rising lambda voltage, so again simply no compensation. I doubt this area is causing the fault.

Yes,i can verify this, one of my precats moved shearing the tip of the Lambda probe,car was slightly rougher at low speeds other than that it was fine,smelly too

[blitzracing]

paulathome said:

Coming to work this morning, the engine started to run rough, very rough.
It appears to have shut down the left bank of cylinders as when I got to work the manifold on the near side was only warm and the offside hot.
Could this be a Lambda sensor fault as its seems to be getting fuel by the stick of petrol but not running.
Had this problem for a week or two, but only after a run and then stopping for ten minuits.
On resart in then seems to be running on one bank only. Its been fine when starting from cold however
until today.
Any ideas guys?
Fitted new coil, ECU temp sensor, rotor arm, dizzy cap, recent HT leads.
The only thing common to each bank are injectors and lambda sensors.
Cheers
Paul.

On second thoughts , pull your plugs out and check the tip colour. Ist possible some simply aren't firing as they are sooted up so its not as simple as one bank is and one is not. Loss of AFM signal can cause very poor running. You can check the outputs with a test meter very easily as you only have 4 wires. Earth, +12, Trim output and and flow output. Trim value does not matter on the catalyst cars (its switched off in the ECU). The airflow output starts at about .7 volts with the engine stopped (ignition on), and rises to about 1-1.7 volts on tickover. If you rev the engine it will rise to a few more volts. Check the RPI site for wire colours.

Mark

[spend]

Do check the heat at the exhaust ports, a very hot manifold can be indicative of collapsed pre-cats,

Dave

[paulathome]

Thanks for all the replies guys.
Jumped in the car tonight to come home from work and it ran a sweet as a nut. (how strange)It did smoke like an number 27 bus when I put my foot down for the first couple of miles though
Guess what my week end will be taken up with?
I'm beginning to wonder if I have an ECU problem, maybe a dry joint or something inside the case.
Or maybe a sensor wire broken between engine and ECU.
Now where the ****in hell did I put my overalls.
Cheers.
Paul.

[GreenV8S]

Stick a diagnostic light across the injector plugs with the engine running, you should see the same output from both banks. If one of them isn't getting switched on, you can then test whether they're getting 12V to see which part of the circuit the problem is in.

[Bensonv8]

Paul,
I had(have) a very similar problem which i've spent ages trying to cure.

Have a look here
http://www.pistonheads.com/gassing/topic.asp?h=0&a...

When the left bank cuts out i can only just maintain 20-40mph and it sounds nasty so i don't like to drive it for more than a couple of minutes.
My quick fix is to dip the clutch and turn the ignition right off for 5-6seconds (until the main ECU relay drops out, you can just hear a click from the passenger footwell.) then i can start it and it's fine again.

i used to switch off, blip the alarm on, blip the alarm off and away we go.
(setting the alarm seems to trip the ECU relay quicker !!!??)


That Daddy, In the above topic (it was a while ago) you posted this comment,............

That Daddy said:

Steve you will get that fixed,i had an intermittant dying at speed like you switched the ignition off(done the 2 relays etc)all seemed fine for 10 months guess what its returned and in aint the relays this time,taking into the workshop tommo, dont you just love faults like this.

Did you have any joy ???

Steve