'97 Mondeo/Contour/Mystique running problem

[Flash]

1997 4 cylinder 2000 Zetec engine. Petrol.

The problem I have is the car stumbling a bit mostly at low revs. It doesn't interfere with revving out but it does with climbing hills.
Iridium plugs and leads are less than 12 months old, new MAF fitted new temp sensor fitted.

When I put the new MAF in it wouldn't idle properly when warmed up so I cleaned the old one and put it back in.

The car runs properly until it warms up.

If I'm driving and it starts to stumble, if I turn the ignition off then back on it will run properly for a while. I'm thinking that leaves out faulty plugs, leads and coil and vacuum leaks.

Any ideas?

 

[BrooklynBay]

Do you see a check engine light?

 

[Flash]

Do you see a check engine light?

I'm pretty sure the '97 doesn't have a CEL, I know there's no OBD.

 

[BrooklynBay]

Every vehicle has OBD (on board diagnostics) with a check engine light indicator. You have OBD-II.

 

[Flash]

Every vehicle has OBD (on board diagnostics) with a check engine light indicator. You have OBD-II.

I don't know why I thought it didn't have OBD2, maybe because the CEL is blown or missing.
I found the port the other day.

 

[BrooklynBay]

Find out if there are any trouble codes stored in the computer.

 

[JMan689]

Contour.org should be able to help.