Question about 1998 Chevrolet Cavalier

1 Answer

PCM Troubleshooting Check light on with no code reader power

Check engine light is on, running rough with no power up hill 40MPH Max. Connected code reader to unit with no power up to reader. Attempted to jump at diagnostic port to flash codes on dash with no luck. Power to A, assuming second spot to jump is reference ground to PCM to force codes to dash, but book doesn't give great detail of wiring to trace back to PCM. Any suggestions or which wires to trace to determine if bad PCM or wiring problem.

Posted by on

1 Answer

  • Level 3:

    An expert who has achieved level 3 by getting 1000 points


    An expert that got 10 achievements.


    An expert that got 5 achievements.

    Brigadier General:

    An expert that has over 10,000 points.

  • Master
  • 4,669 Answers

You can't jump the connector to get codes on OBD II. (Pre 1996) Try hooking back up you code reader. If it doesn't communicate, check the fuse for the cig lighter. This fuse should also power up the diagnostic plug.

Posted on Mar 09, 2009

1 Suggested Answer

  • 2 Answers

SOURCE: I have freestanding Series 8 dishwasher. Lately during the filling cycle water hammer is occurring. How can this be resolved

a 6ya expert can help you resolve that issue over the phone in a minute or two.
best thing about this new service is that you are never placed on hold and get to talk to real repairmen in the US.
the service is completely free and covers almost anything you can think of (from cars to computers, handyman, and even drones).
click here to download the app (for users in the US for now) and get all the help you need.

Posted on Jan 02, 2017

Add Your Answer

Uploading: 0%


Complete. Click "Add" to insert your video. Add



Related Questions:

2 Answers

Troubleshooting a rough idle

Have the engine computer scanned for trouble codes. Misfires are from loss of fuel, spark, or compression. Check the fuel pressure, check that all spark plugs are getting spark, and if all good so far, test engine compression. Low compression in a cylinder will cause misfires and loss of power.

It could also be a vacuum leak- a loose or cracked vacuum hose or an intake gasket leak.

Jul 27, 2014 | Dodge Stratus Cars & Trucks

1 Answer

2003 ford ranger sevice engine light is truck is running alittle rough

If you have service or check engine light tunr on, will need to scabbed the PCM (Powertrain Control, Module) to know exactly what fault code is stored there. With this code number could send you additional details to solve it. Some Autozone or Autoshops with scanner reader codes make this job for free (sometimes).

Hope this helps and just keep in mind that your feedback is important and I'll appreciate your time and consideration if you leave some testimonial comment about this answer.

Thank you for using FixYa.

Oct 27, 2011 | 2003 Ford Ranger Regular Cab

1 Answer

97 Ford expedition check engine light flashing, truck running rough.

A flashing CEL means that you might be causing damage to your CATs. It will flash when the PCM senses a misfire bad enough to cause fuel to dump into the exhaust. When that happens lay off the throttle. Chances are you've got a bad injector or bad plug.

Use a code reader to know the real reason that check engine light come on.

Apr 30, 2011 | Ford Expedition Cars & Trucks

1 Answer

97 Ford expedition blinking check engine light, running rough.

A flashing CEL means that you might be causing damage to your CATs. It will flash when the PCM senses a misfire bad enough to cause fuel to dump into the exhaust. When that happens lay off the throttle. Chances are you've got a bad injector or bad plug.

Use a code reader to know the real reason that check engine light come on.

Apr 30, 2011 | 1997 Ford Expedition

1 Answer

Check engine light is on and it runs rough

You will need to pull a DTC (computer diagnostic code) from the PCM (engine computer). This will require a code reader ($40.00) or you can go to an Autozone and they can pull this code for free. Then, and only then, can a diagnostic procedure begin. The computer in vehicles today have the ability to assist us in repair procedures.

Nov 26, 2010 | 1997 Ford Expedition

1 Answer

I have a 2002 grand cherokee. Was on my driveway backing up (on a incline ) when all of a sudden engine light came on and started running very rough with loss of power. Shut it off then restarted and took...

Your PCM (engine computer) senses a fault code with an engine management component. You will need a codes reader to retrieve the code. If you you do not have a code reader, go to a well supplied auto supply store like autozone, and they will read the codes and let you know what they are. This would be the first step any Tech would do before diagnostic testing begins.

Nov 11, 2010 | 2002 Jeep Grand Cherokee

1 Answer

My Honda avs light comes on along with check engine light, them the engine runs rough? What does this mean?

When there is a code present in the PGM-FI system the check engine light comes on. The VSA system see's this code and stores a code for power-train system failure and turns on its light too. If the engine is running rough you should get it diagnosed ASAP. Some repair shops pull codes for free or you can get a code reader at your local parts store for the do-it-yourself-er. Find out what codes are present and I can help you more if you want to diag it yourself. lmk

Mar 08, 2010 | 2005 Honda Odyssey

1 Answer

Engine light is on and the engine is running rough at certain speeds and climbing up hill

Most likely ignition coils. Not all of them. What code do you get. PO304 as an example. Have a code reader or scanner plugged in next to your right knee under dash and give me the codes

Feb 04, 2010 | 2002 Lincoln LS

1 Answer

Car want pulls hills or any inclines vey well 2005

P0304 code is a cylinder 4 misfire. If the plugs or wires are bad it will cause a decrease in power. I suggest changing the plugs and wires and see if that helps.

Jan 24, 2010 | 2005 Kia Rio

1 Answer

Two dead cylinders no spark on 1 nor 6 cylinders

Based on your readings, the fuel trim of -33 shows that it is running rich on that bank. Disconnect the coil on number one cylinder. With a 12 volt test light connected to ground, probe one of the two wires (engine running). One wire should be hot all the time, then connect the test light to a positive source (battery B+) and probe the other wire. The other sould be flashing on and off while running. The PCM provides ground to the circuit to fire the coils. If you don't have a pulsing light then the PCM circuit is faulty, if no constant power than the coil power source is in question. Don't attempt to fire the coil for testing without a load attached (spark plug) this burns out the driver in the PCM. Check continuity of the driver wire from PCM to the coil, if it is good and the other wire has power then the driver in the PCM is bad and a new PCM is what it will need. I hope this helps.

Apr 27, 2009 | 2004 Dodge Ram 1500

Not finding what you are looking for?
1998 Chevrolet Cavalier Logo

811 people viewed this question

Ask a Question

Usually answered in minutes!

Top Chevrolet Experts


Level 3 Expert

71694 Answers

Colin Stickland
Colin Stickland

Level 3 Expert

22082 Answers

Jeff Turcotte
Jeff Turcotte

Level 3 Expert

7031 Answers

Are you a Chevrolet Expert? Answer questions, earn points and help others

Answer questions

Manuals & User Guides