QuestionHi Roland,
The facts: 3.0 liter engine, 186,000 miles on it
The problem: Vans starts fine. I'm able to drive short distances (up to 12 mostly highway miles in the latest incident). Then van starts to lose power and eventually stalls out, with a slight knocking noise, but not big backfire. I sit for 20 minutes and then I'm able to start again, drive for a mile or so and then it stalls out.
What's been done: New alternator and fuel filter in July 05
New battery,rotor and distributor cap in October
EGR Valve at 160,000 mi
Fuel Pump, Timing Belt, Serp belt, A/C Belt, Headgasket, O Rings, Wires & Plugs at 159,000
I'm in the process of flushing out rusty looking coolant with Prestone anti-rust product - I actually idled the van in the driveway yesterday for an hour, hoping that the bad behavior would show up and of course it didn't.
Check Engine light does not come on. Codes showed 33 7 55. The airconditioner has never worked, so no surprise with the 33!
I'd really like to keep this vehicle going for a few thousand more miles if possible. If I'm going to junk it, I'd like to know that the required work would be more money than what the van is worth to me.
I've had it in at one shop. They took it on two 5 mile test drives and of course the problem didn't show up.
I scanned through your answers pretty closely yesterday and didn't find anything that sounded like this.
I have the Chilton's Manual for this model and do basic maintenance work myself - Anything complicated or requiring more than basic shop tools would need to be done by a professional.
Thanks in advance,
Rebeka
AnswerHi Rebeka,
From what you describe I believe that the code 7 is actually a code 52 (watch for a pause between 5 flashes and 2 flashes). There is no code 7, and so that means it either has to be a 43 (not used) or a 52 that is the code for the oxygen sensor reading at the extreme of leaness and often means that the sensor has gone bad, and that results in a poor mixture at the point in time when the engine controller changes from a preset mixture to a mixture controlled by the sensor, which is when the engine gets up to temperature. That explains the timing of your problem and its resolution on cool down.
The oxygen sensor is located at the outlet of the exhaust manifold and has the appearance of a spark plug. I believe it is on the rear side manifold (near the firewall) rather than the manifold that faces the radiator. It is right where the manifold attaches to the exhaust pipe, in any case. It has 22 mm hex head that you can remove with a 22 mm open end wrench, or there is a special socket that has a full length slot so that the wire on the new sensor will not get in the way of the socket, but chances are you can use the 22 mm open end. The wires have a disconnect plug at the far end. It costs about $75 so treat it gently.
The wires are easily damaged so use care not to stress them.
And apply the grease that comes with the new sensor to the threads but be careful not to get any of the grease on the working sensor tip. To remove the old one you may want to use some penetrating oil on it overnight and rock it tigher and looser to break the corrosion on the threads gradually.
if it hasn't been changed it will be pretty tightly bound in the hole. Torque the new one to the same tightness as a sparkplug.
Good luck with keeping your van going!
Roland
P.S. Thanks for the very complete description of the problem.
