Sludge and starting trouble

We have a poorly maintained 2001 Dodge Intrepid 2.7L with 155,000 miles on it. Over the Christmas break, we left it untouched in the driveway for a month. After that it wouldn’t start without being jumped off, and the oil light flickered when the car idled. We had the battery, alternator, and starter checked at a local shop; all of them checked out fine. Nevertheless, the car wouldn’t start without being jumped off. It would click once, and then nothing. We also noticed it was overdue by 2,000 miles for an oil change, and thought this may be causing the oil light issue. Since the 2.7L Intrepids are notorious for engine sludge, we added a couple of ounces of Seafoam, drove about 15 miles, and then took it in for an oil change. Now it starts without a jump. So my question is Is there any way that oil sludge (and perhaps a weak starter?) is the issue?

how old is the battery? It could just be iffy. After a jump if the lights for the electronics flicker that may just be that the voltage is low, it would stop when the battery had enough of a charge to hold the volts above 12.5 v. Some battery checks are not the same as others. The CCA test is best. It tests the amperage that the battery can support at a set voltage. This tests for bad plates in the battery. I have a ford that I swapped the starter twice before finding that the battery had shorted plates. It would power the lights and all if charged, but even with a jump the starter would do no more than click. New battery no issues for 30K miles. Yes the original started tested bad.
Do not worry alot about the sludge.
If you are lucky it will just stay where it is and the good oil will still lube all the bearings. At this age it is going to be hard to desludge without a teardown which may just loosen stuff to plug up the oil passages that are still flowing. The starting and the oil change are unlikely to be related except for the amount of time you drove the car and charged the battery.

Thanks for the fast reply. The battery is about three months old. We bought it because the old one was giving us similar problems (that battery was at least 6 years old). When we started having the same issues after the car sat for a month, we went back to the local Advanced Auto where we bought the battery, and they said it was good. After needing another jump, we took it to an Auto Zone, where it tested good again. It was tested a third time when we took the car in for the oil change, and it passed. Between tests one and two, we drove it on the highway for 30 miles to charge the battery (the alternator was putting out 13.5V at idle, according to the digital multi-meter). With all those tests, could it still be the battery?

For now, we’re keeping the portable battery charged and taking it with us wherever we go.

Thanks also for the advice about the sludge. We figure it won’t be too long before we’ll need to replace the Intrepid.

Check all battery cables. Make sure they are in good shape and the ends (both ends of each cable) are clean and tight.

And The Oil Light . . . ? If It’s Back Or Comes Back . . .

. . . It’s not a bit unusual to need a new oil pressure sender at this age and miles to take care of the flickering light (if you’re lucky). When the sender is removed, a mechanical gauge should be put in just to test the actual pressure, before putting in the new sender. This whole operation is no big deal.

I don’t recall excatly which years, but I know there’s a bulletin for flickering oil light at idle for earlier Intrepids with the 2.7L (1998 - ?). The problem is a poor connection between the connector and the sender, so be sure and check that out, too. The sender is down near the oil filter.


They’re notorious for oil sludging based on the very reasons you’ve cited; poorly maintained, overdue by 2000 miles for an oil change, etc. It’s not an engine issue, it’s a neglect issue.

Sounds like an electrical fault to me; battery, cable ends, worn starter, etc.

The first thing that should be done for the starting problem is clean the battery connections regardless if they ‘look ok’. If that doesn’t solve the trouble then make sure the battery to chassis ground is making a good clean connection and 12 volts is getting to the starter solenoid wire. The car is getting old enough were the solenoid contacts can be worn out but you usually hear a click each time you try to start up when that happens.