[forjonny]

Seems like when the minivan gets hot then it has issues starting. If I get it started then it grovels or runs rough and I can't get it to rev up. If it does get going down the road it may stall. Getting engine light on when going from 7000' down to sea level or close to sea level. I have a scanner but my mechanic says that those cheap scanners can screw things up. He has a more exensive scanner that works well. We were getting codes for misfires.
So we have checked the wire harness and it looks good. Changed out the squeaky serpentine belt. Checked the cam sensor and cleaned it. Put in a new heat sensor. Put in a new fuel filter with the fuel filter lines on it. This fuel filter new has three lines coming off of it and you have to lower the gas tank to install the thing. I was getting some black stuff out of the old filter.
So gonna drive it to see if it does it any more. Any ideas on why this minivan is doing this? It only has 73,000 miles on it.

 

[AllanC]

I have a scanner but my mechanic says that those cheap scanners can screw things up.

By cheap does he mean scanners in the $100 - $300 price range? I think you need a NEW mechanic. The lower priced do-it-yourself scanners perform READ functions with the engine controller. About the only WRITE function to the engine controller they perform is to clear codes. The accusation is unfounded.

I think you need to resolve the misfire conditions. Did you check the spark plugs to make sure they are clean, properly gapped and center electrode not corroded? With only 73000 miles on the clock this vehicle has sat unused for extended time periods so you may have one or more fuel injectors that are not spraying fuel correctly. They might need to be removed and cleaned thoroughly.

 

[ImperialCrown]

Measure fuel pressure. You can attach a pressure gauge to the fuel rail and with a long enough hose, watch the pressure while driving. I usually hold the gauge under a wiper blade, so I can observe it during a road test (if it isn't raining).
Double-check for any tester leaks before closing the hood and starting out on a drive for safety.
If you got black junk out of the old filter, I would be concerned with how the inside of the fuel tank and f/pump filter sock might look. There could be a contaminated fuel issue. This could be a fuel system-wide problem that might have started inside the fuel tank. A restricted sock would drop fuel pressure under load/acceleration. A contaminated f/press regulator may cause excessive or insufficient fuel pressure.

 

[Ray Green]

Measure fuel pressure. You can attach a pressure gauge to the fuel rail and with a long enough hose, watch the pressure while driving. I usually hold the gauge under a wiper blade, so I can observe it during a road test (if it isn't raining).
Double-check for any tester leaks before closing the hood and starting out on a drive for safety.

Excellent advice IC, especially about keeping the fp gauge outside the cockpit.

 

[forjonny]

So ten days ago I replace the fuel filter like I said and it ran nice until yesterday. I drove it then parked it in the garage for a half hour, started it and it groveled again or idled rough then I pulled out of the driveway and it stalled. I started it went a block and could not get any reving up of the motor. So when I hit the throttle petal it did not rev at all. A block later it recovered and I just drove it back into the garage and parked it.

So apparantly it was not the fuel filter I suppose.
I have put some Lucas fuel injector cleaner in it as well. My checker was only about $35 on Ebay. My fuel pressure is around 27 PSI but was about 20 before I changed the filter. My mechanic says that is should be around 30.

 

[fjb37]

Your fuel pressure should be around 48 PSI. I think that your problem is in the tank and IC has it right and your "mechanic" is FOS! Just my $0.02.

FredB