Sputtering & hacking

:banghead:My '00 Silhouette exhibits the same exact issues scottp6 did in this thread http://www.automotiveforums.com/vbulletin/showthread.php?t=951953

Checked all connectors under the van related to the fuel system...all perfectly clean w/ no corrosion, replaced spark plugs (cuz it needed it anyway) and then after reading the above thread figured I would take a shot at replacing the fuel pump...easy peasy job, van idles smoother and more responsive to very small gas pedal inputs...u try to floor it and it sputters & coughs...won't pick up speed on the road very well...get the flashing service engine soon light....

any ideas

david

A flashing SES light is a bad thing, it usually means that a cylinder miss has developed that can cause raw fuel to bypass the combustion process and get into the exhaust and destroy your catalytic converter.
You didn't mention how many miles you had, but since the plugs were due, I'd guess over 100K since that's the suggested change interval.
I just finished a far to long reply to psivver on his engine shake and miss at idle. I am going to cut and paste it here since it's after midnight and I don't want to go through it again.
Pick and choose the parts which apply, my guess is it's ignition wires (since you changed the plugs) or O2 sensor causing you to run lean or rich and causing the miss. So here it is:

The idle on my 98 with 390000Km (hope I did the math right) is between 800 and 1000 RPM. In the olden days when we had carburators I would say you had a vacuum leak leaning out the idle mixture, but today with the computer controls all that would happen is the injectors would add more fuel to keep the mixture correct and it would increase the idle speed.
At 160,000 km (100,000 Mi for us down here), have you replaced the plugs, wires, and O2 Sensors. I had an ignition wire fail and it caused a miss in unusual conditions (accelerating after a descending left turn) after several attempts at a particular off ramp it finally set a code for a cylinder miss on #6. It was a bad ignition wire, when they fail the fiber core of the wire melts and becomes resistive and you don't get as much spark. You can do a resistance check on the wires and look for one that has a higher resistance than the others. But all in all, don't work too hard at diagnosing it. If the plugs and wires are old, just replace them (100,000 Mi (160,000 Km) is the suggestion).
I also had an O2 sensor fail causing the engine to quit on acceleration from a sweeping right turn. Sounds like a freeway on-ramp, nothing more exciting than entering traffic and have your engine quit with a bunch of cars behind you.
It seemed that the sensor had shifted its calibration point and was leaning out the mixture just a bit, when I turned it must have dropped the fuel pressure a little bit, and the combination was enough to kill the engine.
Your Van will have 2 sensors, the one upstream(closest to the engine) controls the fuel mixture. The downstream sensor just monitors the output of the Cat Converter and dosen't have much effect on the van until it really fails and set a code. It's recommended that the sensors be replaced about every 75,000 miles.
Also there is the Air Filter, MAF(Mass Airflow) sensor, both in the air intake which can become plugged and the EGR(exhaust gas recirculation)valve that can stick open and continue to recirculate exhaust gases into the intake, which can really foul up the idle.
Come to think of it, the EGR might me my first choice. The EGR valve is a variable valve that normally opens to control the temperature or the combustion to reduce nitrous oxides (NOx). It has been noted that carbon build up in the valve will cause it to stick open when a small chunk of carbon blocks it. This would allow exhaust gases to be fed back into the intake at all times, but would affect the idle most.
The EGR is in the back of the engine next to the Transmission dipstick. It is black and stands up and has a 5 pin electrical connector. It's held down with two 10mm bolts, one has a stud top to hold a nut to attach the Trans dipstick. It's not a big job, be prepared with a new gasket (a buck or so) and try not to disconnect the exhaust feed line below the valve mount, it can be a bear to get back on. When you get it off look at the bottom, there are two holes,inlet and outlet, one is blocked by the valve. As I remember you can push the valve open against spring pressure and blow out any carbon particles with canned or compressed air (SAFETY GLASSES PLEASE) than reinstall it and hope you were right.
These are all covered in the Haynes Repair Manual which for $20 US or so is well worth having if you plan to keep the van. My book is #38036 and covers years 1997-2001 and will probably work for you also, or you can go to their web site and get the correct book.
Well good luck, let us know what you find, feedback is always helpful.
94

Thanks for the reply and info on where to look.
It will be a few weeks till I'm back home and able to work on it...
- 2000 Silo w 123,000 miles
- Plugs were replaced, old ones looked good with a slightly larger than spec'd gap...just worn out I guess...
- Resistance test showed six good cables
- Van runs rough and doesn't like hard acceleration
- IF you can get up to highway speed big hills or the freeway on/off ramp is a scary thing

Will try the O2 sensors!

david