Battery light is on and alternator not working on 1997 Odyssey Honda with 2.2L engine: No codes

Question:

My wife's 1997 Honda Odyssey battery light is on all the time and the alternator won't charge. I replaced the alternator with a rebuilt one from our local parts store but the problem is still there. A friend mechanic told me to replace the ecm (computer) but I am not sure if this will fix the problem. Can you help?

ATS adviser:

There is an electrical load detection (ELD) unit located at the fuse box under the hood. Check the pin wire #2 with grn/red color and see if it is connected to the pin#16 in your ecm. This is a control wire from the ecm to your alternator. To check, run a jumper wire between those pins and if the alternator starts to charge, replace the alternator. Finally, if you bought the alternator locally and not from Honda, I guarantee your alternator will not work.

ATS tip:

When testing the LED unit, make sure the ground wire at pin#1 is clean and secure. To get the wiring diagram for the charging system, contact ATS.

P0303 misfire code for 1997 Ford Wind Star with 3.8L engine

Question:

This 1997 Wind Star is having a misfire code after the engine is warmed up. When scanned there is no coolant sensor code except this misfiring code. The engine has a lot of mileage but when we checked the compression, readings are all above 140 psi. No engine coolant was found in the oil and I think the engine is fine. testing the vacuum confirms that the reading is well above normal.

Testing the injectors shows the same reading and when I checked the spark quality while idling, I have a steady blue strong spark. I am now inclined to suspect that we might have a computer problem. Do you agree?

ATS Advisor:

There are a few tests you can do on this code: 1.) try switching the plug wires and see if the misfire code will change to another cylinder. 2.) did you clean the mass sensor? usually this will not cause a misfire code. 3.) tried disconnecting the egr valve? if misfire stops, then egr system is faulty. 4.) if all of the above fails, remove the intake plenum at the intake manifold and most of the time, the seals and O rings for this plenum leaks causing a misfire code when hot.

Car hesitates on 1999 Cavalier with 2.2L engine: No codes

Question:

I have a 1999 Cavalier and lately, I have an intermittent hesitation and misfiring and the check engine light will come on in the dash. However, if I scanned it, my scanner will not communicate with the engine computer (ecm).
What do I do?

ATS Advisor:

There is common cause for this problem and it is attributed to the poor location of the ecm. If you look under the front fender of the car and remove the cover, you will see the ecm. A lot of times, because it is too close to the ground and rain water when you are driving, the wire terminals to the ecm will be corroded. When that happens, the wires will be covered with "green stuff" and later the wire can have a poor contact or even break. Try wiggling the wires to the ecm and find which wire is broken. Repair if necessary.

If the ecm will still have no communication with your scanner, remove the ecm and test all the ground and power supply wires as per ATS past newsletters (testing ecm). If the readings are normal and reference voltage is erratic, replace the ecm.

ATS Tip:

To get a detailed wiring diagram of your ecm, please contact ATS.

P0402 code for 1999 Nissan Altima with 2.4L engine

Question:

Have this code P0402-egr control back pressure transducer valve on my Altima and when I tested it, found the egr valve sticking. Replaced the valve and also cleaned the passage tubing going to it. After resetting the code and road testing it, the code light went out. however, after a week of using, the same code came back. I re-check the egr valve and I cannot find anything wrong. Please help.

ATS Advisor:

When testing your egr system, try these:

Check all your egr vacuum hoses for cracks and connection

There is a restrictor inside the vacuum hose for the EGRC-BPT valve, that cam be tested for dirt restrictions due to carbon

The egr valve flow can be tested by lifting the spindle with your finger during idle and the rpm should go lower.

If the above code persists, replace the egrc-bpt valve next to the egr valve.

Code P0301 on 2001 Pontiac Grand Am with 2.4L engine

Question:

My 2001 Grand Am has a misfire code P0301 when scanned. The engine was also quitting at stop lights. Initial repairs included replacing the spark plugs that included the ignition coil. After doing all of these, misfiring is still present and I am now thinking of replacing either the ignition module or the engine computer. Any suggestion?

ATS Advisor:

The most common cause of this misfiring is a shorted ignition coil housing. When you replaced the spark plugs, the housing should been checked for heat burns on the housing which will verify such condition. shown on top is a picture of the housing. If you invert it, most heat burns will occur between the spark plug mounting holes.

Code 32 on 1990 Corsica with 3.1L engine

Question:

This 1990 Chevy Corsica has a code 32-egr system fault after I scanned it with OBD1 scanner. When I checked the egr system, I found that I have an egr electric solenoid instead of an egr valve. How do I proceed to test it?

ATS Advisor:

To check the egr solenoid is quite simple. start and run your engine at idle and put a jumper wire on each of solenoid 3 wires. When you do this, each solenoid will be activated causing it to open up and should cause your idle rpm to change. If all 3 solenoids do not make any changes, stop the engine and remove the egr solenoid. When removed, check first for the opening where the solenoid was mounted. If the hole is clear of carbon, replaced the solenoid, otherwise clean the egr passage hole.

ATS can supply you the wiring colors of each egr solenoid wire.

Serpentine belt installation for 2003 GM p/up truck: No codes

Question:

This truck's engine serpentine belt was sqealling and before I could replace it, it broke on me, how do you replace it?

ATS Advisor:

If you open your hood compartment of your truck (see picture) you will see the diagram of the serpentine belt routing. You can follow that and when you buy a new one, the package of the belt will also show a diagram for it. Make sure you give the parts store the accessories that you have like AC so they can give you the right lenght of belt.

After market water pump for 2003 Honda Civic has to be changed twice in the last 3 months: No codes

Question:

Why would my water pump started to leak 2 weeks after I replaced it and AGAIN after almost 3 months? I bought this water pump from a local parts store and I also flushed the cooling system to make sure the coolant circulating is clean (engine has over 100k miles). Do I need to use a special coolant for this vehicle? Your insights would be highly appreciated.

ATS Advisor,

First of all, stay away from after market parts when dealing with imported vehicle like Honda. You can buy an OEM (original) part from the dealer and you can avoid all this head aches. when replacing the coolant, use the one recommended by the dealer and mix it 50-50 with water. If you need more assistance, just contact ATS.

P0123 TPS Code for 2000 Jeep Sport Cherokee with 4.0L engine

Question:

This 2000 Jeep Sport Cherokee has this check engine light coming on and when scanned, a code P0123-tps voltage abnormally high showed up. Ever since this happened, my cruise control quit working and the engine keeps stalling making it difficult to drive in heavy traffic. Measuring the tps voltage using ATS wiring diagram showed the tps is defective. We replaced the tps sensor but it did not fix anything. Thinking it might be the computer, we replaced that too and STILL the same code! Please help!

ATS Advisor:

This is a common problem and you should have contacted ATS before you replace those parts. The problem here is a faulty clock spring hooked up to your steering column. What is happening is the clock spring circuit is shorted and it is also connected to your tps circuit. To test, unplug the connection to the clockspring and your tps should work. Most of this problem is usually solved by replacing the clock spring. If the clock spring is fixed, it will fix the cruise control also.

ATS Tip:

A step by step procedure in replacing the clock spring is available from ATS if you are a member.

P0171 and P0174 codes for 2000 Hyundai XG300 with 3.0L engine

Question:

This 2000 Hyundai XG300 runs pretty good but 3 days ago, the check engine light showed up accompanied by codes P0171-Bank 1 system too lean and P0174-Bank2 system too lean. My vacuum reading looked normal and I did a quick tune up like replacing all filters and spark plugs. Since the oxygen sensors have not been replaced since the car was new, I replaced both the upstream sensors. The downstream sensors (after the CAT) are not used to monitor engine fuel mixture so I left them alone. However, after doing all of these, the light came back with the same code. Suggestions?

ATS Advisor:

The most common cause of this problem is a dirty or faulty mass sensor. You can service that by cleaning the sensor wire elements as per ATS course. If you see any improvement after servicing but the code returns after a few days. Replace that sensor too. In case this fix will not work, here are other areas to explore:

Are you using premium gasoline? It would help if you it and may also improve performance.
Have you done fuel chemical tune up? If the engine has too many miles, the injectors could build up varnish and ultimately carbon in the combustion chamber causing this lean condition.
Adding chemical additive to your fuel tank can help remedy this. however, if the code persists, have the injector serviced by a garage.

Code 41 with severe stalling on 1993 Dodge Caravan with 3.3L engine

Question:

My minivan has poor power accompanied by hesitation on acceleration and stalling on stop signs. When scanned, I have code 41. I have checked the engine for mechanical condition and seem OK. Using your ecm test, I found the engine acting up when the ecm is tapped with a rubber mallet. I decided to replace the ecm and it worked good for a couple of days. After that, the problem returned with the code 41. Please help.

ATS Advisor:

The first thing I would check here is your alternator. There are a lot of reports indicating this is a common problem especially on high mileage minivan with this model. Check the alternator for proper ground or have it tested for proper output. If this won't fix it, have the bcm tested also for ground connections. If you read my earlier blog, bcm testing is discussed extensively. Always reset the ecm every time you perform any repair.