2005 Chevy Cavalier Has Trouble Starting After Being Driven & Hestitates Driving

Clogged/collapsed converter or muffler?

A few questions are needed to appropriately answer...

What is your physical geographical location...

Please give a brief but accurate to your knowledge description of vehicle maintenance during the last 5 years, services etc..

Has fuel economy changed over the past 6 months and how so...

What is the overall condition of the car including mileage...

I'm about an hour from Philadelphia. I bought the car new, and I have kept up on oil changes, etc. It has 159,000 miles on it. It hasn't had any problems up until last year. Last November it had the timing chains changed on it. After they were changed the car never idled right, and the mechanic told me it had a misfire in one of the cylinders. He told me it wasn't worth fixing so i've been driving it since. I did take it to autozone last night, they scanned it because the check engine light came on. It scanned as an 02 sensor. The misfire didn't even come up. I have heard to 02 sensor won't cause the problems i'm having though. Fuel economy has been normal. It did go through a brief period of running rich and lower gas mileage about 6 months ago. I took it in and they couldn't find anything wrong with it. It seemed to have corrected itself soon after that and is fine in the aspect still.

All things considered it seems you may have been taken advantage of by the mechanic that changed the cam chains as Tcmtech indicated in his thorough description.

Bought new and responsibly maintained, I'd expect the engine would exceed 300,000 usable life, so it's a little over half in the bag and may have a half life; another 150,000 miles remaining.

Peruse Tcmtechs post and have the car inspected by a reputable mechanic and the dealer or a quality car care center is a good place for the inspection. Then you can make an intelligent decision with the results of the inspection. The level of expertise at the dealer could be advantageous if actions are take against the other shop.

Give a heads up when you have the results in hand

It kinda sounds like something is leaking down and flooding the engine. I would start with a fuel pressure test, then wait and see if it leaks down in to the engine while it sits. Injectors and fuel pressure regulators can sometime leak and cause the symptoms you are describing. Another possibility could be the car thinking its cold all the time and dumping fuel accordingly.

This is not an all-inclusive list, and it is possible under some circumstances to add or delete items. It is a basic performance testing menu.

Basic testing sequence:

Pre (cold) start attempt:

Check for proper battery voltage

Install fuel pressure gauge

Check for pressure and volume (check spec table in repair manual)

Install engine analyzer

Check for spark at a minimum of two cylinders

Check for injector pulse at a minimum of two cylinders

Pull codes

Check ECM/ECU data stream

Attempt to start: if starts and runs:

During running, recheck:

Fuel pressure/volume

Primary/secondary ignition scope traces

ECM data stream

Similar problem encountered in 2005 Chevy van with 160,000 miles. Problem was clogged catalytic converter and bad O2 sensor. You should always replace O2 sensors in pairs, i.e. if you replace one on the right side you should replace both O2 sensors.

Thank -you

from Guest (post) #1

(repair shops always seem to neglect/forget the exhaust system when diagnosing these things - and wild goose chase, spending lots o' troubleshooting money)

Here another area to check. The ignition module and/or coil pack.

I had a 1996 Oldsmobile w/3.6 ltr. engine. I had very similar problem it showed it's self in hesitation and missing then hard to restart if driven for some distance. Then it would not start unless it set for several hours. I found the ignition module was dripping some black goop. I made the mistake of touching the housing it was HOT!

Later after I got it home then I removed the coil pack most if not all of the epoxy potting had lquidfied and leaked out. One or more of the transistors,mosfets, was bad.

So I replaced the ignition module and also the coil pack since it had been subjected to high heat also. (I found a crack in the housing also)

And just for good measures I installed new plug wires and spark plugs.

After that the car ran great picked up more power (I had not noticed how much it had lost!) fuel mileage went up 3-5 MPG city/hwy. Wife was happy to have a dependable car and not worry if she was going to get there or back.

Its was an easy check to take the coil pack off it was 4 or 6 screws lift it up and look if the potting is missing or looks like it has flowed out you may just have found your problem. If you drive the car for a few miles then do the check I don't think you could touch it. If you could remove the coil pack the epoxy would be very soft or even liquid.

Hope this helps you.

Charles

stop using shell gas! If u are I dunno why but my guy that works at gm says the addative they use is bad for ur engine... fuel system, use chevron#1 or esso but not shell in a gm! Sounds like maybe o2 sensor? shell will kill that quick.