Pinto EFI running problem

[Po79]

Hi guys,

I have been hdifferentissues with my Transit van with a 2.0 EFI engine.


It failed the MOT on high HC emissions so I changed the HT leads, dissy cap, rotor am and valve stem seals. The spark plugs we'd fairly new so not changed.


After doing the above the van started fine but after being left running and getting hot the engine started running rough revving up and down to the point of almost stalling, turned it off and checked it over tried to restart but it just wouldn't fire up.


It would only restart from cold with the dissy advanced and when it did it was running rough again revving up and down.


Rechecked the valve clearances before the engine was fully cooled and the clearances were all spot on.


Doubled checked everything else and then started checking the sensors.


When I took off the MAP vacuum pipe the engine smoothed out but still not right (still needing timing advanced) so fitted a new MAP sensor and EGR sensor but this made no difference once connected back up.


So the engine only starts up with the dissy advanced but runs rough whilst keeping the MAP sensor connected, turn the clockwise to retard it and it will run fine with the MAP sensor connected but will still stall once the engine gets hot.


I still keep thinking the issue is the valve clearances but the were right when I did them and right when I checked them, I just keep thinking that the valve are heading up and not fully closing but it can't be.


Anyone ever come across this or have an idea what might be going on.

Does the 1.6ltr cam use different valve clearances, I thought they were the same 0.20mm inlet and 0.25 exhaust?


Cheers,


Po79.

PS my strobe light is bust so have been adjusting it statically and by ear.

[Po79]

Just to add that the plugs are sooted black.
I'm guessing that with the MAP vaccum pipe off and the plugs black then its running rich.
I'm just a little lost.
I would like to test the TPS and manifold water temp sensor, I've ran the engine witht the TPS disconnected but that didn't seem to make any difference.
Cheers, Po79.

[katana]

No expert but the MAP should with the mapped fueling reduce fuel at idle as vacuum increases here - disconnecting it with therefore richen it. There should be something in the ecu to allow cold starts ie gives extra fuel while cold with numbers diminishing as engine warms up based on time / revolutions from start / temp. If the engine coolant sensor is dicky it could cause the symptoms you have? Its like pulling the choke on a warm carb'd engine!

[Po79]

Thanks Katana,
Any chance you would know how to test the water temp sensor.
Removing the MAP vacuum pipe must be leaning the mix up so if it is over fuelling then the MAP sensor isn't able to over ride or cancel out whatever else is going on.
You'll have to excuse me this really isn't my strong point.
Any thought on the valve clearances, if they are right then these really should be an issue but it seems funny this started after doing the stem seals.
Cheers,
Po79.

[katana]

Testing sensors is usually a PITA unless you have the output spec's. For what they cost, replacement maybe better option / more viable? An open vac. pipe will certainly lean off the mixture hence why it ran better and faster!

Re clearances - on a cold engine with a std cam - inlet 0.008" / 0.20mm, ex 0.010" / 0.25mm

[Po79]

Thanks.
I'll see if I can find some old threads that may help with the testing.
That's the valve clearances I used and I got the same when I check with the engine still a little warm so they can't be too tight.
If I can't test things properly then I'll have to just replace the sensors just don't really want to do it aimlessly and waste money.
Cheers,
Po79

[Matte]

Is it the same EFI as on the Sierras? Does it have an oxygen sensor? In that case i you have to put the ECU in a test mode to set timing properly.

[Po79]

Hi Matte,

Its got an oxygen sensor before the CAT so I guess it's the same. How do I put it I to test mode.

I realised after that I already had a page from this forum open about the testing but it says pin 43 at the ECU should be for the AFM but I've got no wire in number 43.

I'm guessing I can just trace the wire colours back to the right pins.

Cheers,
Po79.

[Po79]

Just checked the tps at the ecu pin 47 white and blue wire and I'm getting 1v at idle and 1.90v at fully opened.

These values are from what I've read wrong and should be 0,5v at idle and 5v fully opened if that's right?

Only thing is divorcing the tsp doesn't seem to make any difference.

Got to try and pick up a new timing light as mine is now in the bin.

Po79.