2.0l Pinto Efi Tuning

[Guest MacMustang]

At what point did the engine stop running at all? In your first post it seems to be running albeit badly, and now you can't even get it to start. The first thing to do therefore needs to be to go back over the things you've done since it was running and undo them until it runs again, then change one thing at a time and try to improve it. Check your plug leads and then check them again. Its very easy when you're fiddling about taking them on and off to put them back in the wrong place on the distributor, make sure the right one goes to the right cylinder.

An air leak between the filter and the MAF will not cause problems, but an air leak between the MAF and the engine will (but this will cause it to run lean - unless it has been 'adjusted' to compensate for the leak in which case it may be variable in mixture, to rich in places, too lean in others). You say the filter appears unsuitable, what do you mean? If it's overly restrictive this may be a problem, try running it without one while you're testing, but do get round to fitting a new one before you start driving it around.

Check the resistance of the temp sensor, I don't know what the value should be, I've lost my Autodata CD which would have told me unfortunately. However if it reads open circuit or short circuit (ie no resistance or infinite resistance) then will be a problem. I doubt this would stop it running at all but it could cause your bad running earlier.

Try disconnecting the ECU (or unplugging the battery) for a few minutes and then reconnecting it. If you've been unplugging things while its been turned on it will think there's a fault and enter limp home mode. if you unplug it it should clear its memory and reset it.

I have heard that to get an engine like this where you don't know the timing started you should try gently turning the dizzy back and forth while someone else cranks it over. When it catches and runs then you can time it up properly with a strobe.

EDIT: That's also a good point space ace. If you've had the belt off then check all the timing marks (crankshaft, camshaft, dizzy drive sprocket) line up.

Cheers timswait,

 

Well funnily enough it was working with the airfilter on (with a leak) but hasn't really worked at all with out the filter. I didn't think that running without an air filter would be an issue but maybe it is.

 

The problem with the air filter is that the MAF has been mounted to the chassis using a bracket and two of the bolt holes for the air filter. When the air filter was mounted, washers were used on the other two bolt holes and some sort of putty was used to fill the 1mm gap between the filter and the MAF. This putty had started to degrade. I want to extend the bracket and mount the maf using the correct bolt holes.

 

As changing the spark plugs gave a better result I wasn't sure if the coil was on its way out and not producing a strong enough spark. I'm going to get someone to help me with the dizzy tonight whilst the engine in cranking.

 

Last night when I checked the timing belt again, I accidentally moved the distributor CAM. I take it that this doesn't matter? I couldn't see any timing marks on it? When I went to line the rotary arm up with HT lead #1 I realised and moved it back to about where it was...

 

The saga will continue tonight!

[Guest timswait]

Last night when I checked the timing belt again, I accidentally moved the distributor CAM. I take it that this doesn't matter? I couldn't see any timing marks on it? When I went to line the rotary arm up with HT lead #1 I realised and moved it back to about where it was...

That would be the problem then! It most certainly DOES matter where the belt goes on this, otherwise your ignition timing will be way off, which sounds from your description to be the case- I would guess from your description of it's running or lack of that it something like 45 degrees off! There should be some sort of timing mark on the dizzy sprocket although I can't say from memory what it is. Hopefully someone else will know. Get the three things (crankshaft, camshaft, dizzy) on the correct tooth of the belt and you should at least be in the right sort of ball park for the engine to start. With it running then time it up properly with a strobe.

Don't get distracted by the air filter at this stage, it won't be what's stopping it running. There is also a mixture screw on the MAF sensor, but don't start fiddling with that until you get it running at least as well (or badly) as it was before you started on this saga, and if you do start fiddling with it make sure you count the turns on any adjustments you make so you can get back to where it was.

[Guest FIRSTBUILD]

I've checked the timing belt a couple of times now and when cylinder #1 at TDC (crank pully at 0) the arrow is maybe 2mm off the dot. Unfortynately this must be where the belt has stretched as moving it to the next tooth moves the dot more than 2mm the other side of the arrow. Head is original.

 

Last night I replaced the spark plugs and got it to fire and kind of idle but it didn't sound like it was firing on all cylinders. Trying to increase the revs made it die and eventually it died any way.

 

 

to check the temp sensor under the manifold just remove a tiny bit of the insulation on both wires - set your meter to meaure dc volts and connect -- the voltage is really low when its cold and only rises a couple of volts when it warms up.

 

I would really think its the ign timing - remove the rocker cover and look at the cam - remove the plug and look?feel where the piston is then look at the dist. and cap --- think it through and try again mine took ages to set.

 

the cambelt usually looks a little bit out due to tension - if its a tooth out you would really see it and I dont think it would hardly run.

 

my efi has always smelt rich on tickover - my ten year old daughter wont ride in the "smelly" thing !

 

hope this helps

 

Steve

[Guest MacMustang]

It's alive!!!

 

Thanks for all of the advice guys. Seems I must have got it pretty close the other night as I got a friend to turn the dizzy whilst I was cranking and all four cylinders came to life and it starting purring

 

Bought a strobe last night so will set up the correct advance. According to the manual it should be 12° BTDC for the 2.0L EFI but 8° for unleaded... is that correct?

 

Thanks again for all of your help and advice.

 

Adam

[Grizzly]

... According to the manual it should be 12° BTDC for the 2.0L EFI but 8° for unleaded... is that correct?

I'd go for in between 10 & 11 degrees.

On mine, anything less than that caused popping in the exhaust on the overrun.

This should be close enough until you can get it tuned on a rolling road.