S1 2.8 idling

[niels]

Hi,

I had my 2.8 engine replaced a week ago (head gasket blown etc.) with a late '86 2.8. The new one runs better (less noisy under the bonnet) in general, but at tickover (1000 rpm) it doesn't run smoothly. Also when hot, the idling rpm drops to 700/800 and finally the engine cuts out.

I've tried to adjust the idling rpm as a temporary solution, but turning the screw didn't have much effect on the idle rpm.

Also, I discovered that the air hose is a bit crappy at the throttle intake (so maybe some false air?)

Besides the idling, the engine runs great when driving normally and runs and performs better than the old one when applying the right foot..

Could this have to do with the mixture/CO ??

Thanks & Cheers

Niels
S1
Netherlands

[martyn-s1]

You might want to check that the servo vacuum pipe is on fitted correctly or not leaking as I had similar uneaven idle problems, but not cutting out. When I changed the servo, as the old one had some rust holes in the bottom and failed MOT, the uneaven idle went away as I assume the old servo had not been vacuum tight and was letting air into the engine.

When running the engine without the vacuum pipe connected to the servo the engine was struggling to keep running.

[M@H]

The intake pipe to the plenum butterfly is after the air flow sensor plate. If there are any splits in this pipe at all, then the plate will drop lower than it should as air is being drawn through the splits, rather than past the plate. This will show up on idle if the split is small, if its big, then the car will try and stall at anything under 2-2500 RPM.

I went though this with my S1. The other thing that springs to mind, due to your comment on the engine being hot is that your Warm-up regulator could be playing up.

Cheers,
Matt.

>> Edited by M@H on Friday 8th April 15:19

[old64er]

You may find that it is the fuel control flapper in the airbox.
If at tickover the flapper drops too low or is sticking then the idle will become very lumpy and usually they cut out.
If it drops below the factory setting then not enough fuel flows through the fuel distributer and up the injector pipes and it cuts out.

i was a common complaint on old granadas as i remember from my MOT testing days.
It usually happens when they are up to temp and the 7th (cold start) injector has cut out.

You can adjust the seat depth of the arm by removing the air filter and persuading the stop a little.

Hope it helps

Surprised you didnt mail me