Manager Forum

We currently have a 99 villager in the shop that has us all stumped. It runs like a champ when it's cold but the once it warms up it stalls and misses. We have replaced the CPS, the O2 sensors, cap rotor plugs but it is still acting up. Weird thing is that if you remove a wire off of the plug it will not throw a mil light. I even went as far as unplugging the bank 1 O2 sensor and it still will not throw a code. I'm thinking PCM but I'm not to sure. Any help would be much appreciated.

Why were the parts replaced? What test have been done? Which cylinders does it misfire on?

It came in stalling at an idle the downstream O2 sensor was not working. Fuel trims were way off. Replaced the O2 sensor and the fuel trims came back in line with no mil light. But once it heated up it continued stalling. We checked for vacuum leaks and none were found. I failed to mention that this van only has 79k on it. Checked all grounds and all are good.
Road tested it and it runs down the road fine. But keeps stalling on idle when it is warmed up. MAF sensor is good, Coil is good. Compression good. Fuel pressure good. The temp sender is good. But for some reason it keeps kicking scanner out too we have a genesis evo.

The fuel trims are ok when the stalling happens?

If the fuel trims are good id lab scope the distributor

Fuel trims are great. Down side we don't have a scope. Any suggestions?

Hmm ya id replace the distributor if I was a gambler id say its 90% chance its your problem.

A few things on these beauties. I lost count of how many air flow sensors that tested great but were bad. The first one I had with this engine threw me for a loop and I had one come in the next day for service so I started swapping out. The mass air flow sensor did the trick. There are a few sensors that don't activate until it reaches operating temp. I've had IAC's do this, try tapping it when it's doing it. Pulling a plug wire or an injector wire on these early Fords / Mercury's will not necessarily throw a code, not necessarily may be to kind of a word, let's use probably never. I would check all of the above plus see if you're getting vac to my favorite stalling at idle when warm buddy the good old EGR. If this isn't the issue then I would go with a distributer. I'm assuming you sprayed carb cleaner all around the intake. I've had bad lower O rings on injectors do this as well as cracked intakes near throttle body.
When it reaches operating temp it throws you out of the on board diagnostics my lead me to investigate what sensors are activated when temp is reached. One may be shorting to ground causing the pcm to kick you out. Don't bet the barn on it but I think on early vehicles like this there may be two or more sensors per circuit. good luck

Thanks for all the tips. We will give them a try this morning first thing and let you guys know what we come up with.

brianp87 wrote:Hmm ya id replace the distributor if I was a gambler id say its 90% chance its your problem.

I have to agree with this. The other thing ya might try is to clean the disc in the bottom of the distributor. I have seen several driveability issues solved by doing this.

Well Gents it runs like a champ. Pulled the distributor and put it on the bench. From first glance it looked fine. I took the cover off of it to find it full of metal shavings. SO replaced the distributor let it run for 45 minutes watching the scanner data and it ran great. We thank you all for your help. We will be on these forums from now on to help contribute our help just like you guys did. Once again thank you all!

Always good to have new blood on board.

Nice