zoltan

I just bought a 92 Maxima with the DOHC engine, no rust, and body is perfect. with only 240 000 km, with new pads and rotors and alternator and battery, for $150 (AC even blows ice cold) . It was going to be crushed and what a shame that would have been. This is my first Nissan, I bought the car real cheap because I was told that two ignition coils are bad (one froet and one rear). It starts and runs very rough. There is a diagnosis is from a repair shop that says two coils are bad but all six should be changed, the shop did not specify which two coils are bad. Can anyone point me in the direction of how to use the OBD to tell me which coils are bad. Thanks for your help, it is much appreciated. Zoltan from BC Canada

DennisMik

iTrader: (2)

The third gen Maximas had OBD I and it was rather limited in what it reported. Finding an OBD I reader now-a-days is a challenge.

To find a bad ignition coil, start the engine and unplug the wire connector for the ignition coils one at a time. If you unplug the wires on a good coil, the engine will run worse. If you unplug the wires on a bad coil, there will be no change on how the engine is running.

zoltan

Thanks a bunch for taking the time to reply. I will try that. I am just worried, because it runs so bad now that I wont be able to tell.

ac max 92

iTrader: (13)

You should still be able to tell if only 2 are bad. This section is getting pretty quiet so trying to find a used set quickly by posting a want to buy ad in the classifieds here may not happen as quickly as you may want the coils though the good news is they are still available new. Either check an aftermarket parts supplier like rock auto or maybe even try eBay. There was a member here with a used set but he hasn't replied to his classifieds ad for some time now.

zoltan

Thanks so much! I will be working on it later today, and I will post my results! I did find some on rock auto and ebay!

zoltan

Thanks so much! I will be working on it later today, and I will post my results! I did find some on rock auto and ebay!

zoltan

I let the car warm up to full temperature and then unplugged each individual coil, and it did not seem to make a difference, I drove the car hard for 5 min and it felt like it was running on all 6 cylinders just fine. Then all of a sudden I lost 90% power and limped home a mile and the last 500 yards is up a step hill, the car barley made it up the hill while shaking real bad. I shut if off and it will not restart. Any one have any ideas? Thanks for taking a look.

Tarzan

Move coil packs around one at a time and see if misfire follow.
You should be able to visually inspect coil packs for cracking - cracked ones are usually bad ones.

It feels like camshaft or crankshaft position sensors are bad in your case.

Did you check the plugs themselves? Is there any oil in the plug wells and on the insulators? And compression check is due of course.

zoltan

I did visually inspect each coil and no cracks. There is a bit of oil in a few of the plug wells. I did not pull the plugs. Could the obd tell me if the crank or cam sensors are bad? I need a good writeup on how to use the obd. Some people say you need a reader? Is this true? Also does anyome know the the cam and crank sensors are specific to the VE30DE motor or could I find them on another Nissan as I cant find that motor in any PIck and Pulls. Thanks again for everyones help, it is greatly appreciated. These cars seem to be very rare in the West. I live in Kelowna BC, and the car lived on the west coast most of its life. It has ZERO Rust, and the body is perfect. It would be a shame if I cant get it going. If I cant get it running for cheap, I will be selling it for $300

ac max 92

iTrader: (13)

If you have oil in the plug wells you probably have leaking valve cover gaskets which if too much oil gets in there you can lose power too. The ecu on these cars only really throw a check engine light when there's an open or short circuit. If you have a check engine light on you can read the codes manually by counting the flashes on the lights on the ecu. You can find the factory service manual and it will show you how to read the flash codes and give you the definitions of the flash codes. If you dont have a check engine light on then it's pointless and it won't tell you anything. The only other way to read the codes is with a consult unit that usually only the dealership will have If they still carry them. The port is not ob2 it's obd1 and has a different connection. Cam or crank sensor could also be a part of your issue. If your planning on keeping the car start with a good tune up and change those valve cover gaskets if you also see signs of oil staining on the heads below the covers. Then move on to diagnosing your sensors. Check the factory service manual for the specs on the cam and crank sensors and check resistance to see if they're in spec. If you unplugged your coils one at a time with no change in idle then they're probably good. You should start hearing a change from a misfire if you unplug a good coil and no change if you unplug a bad one. You could probably test resistance on them too if you check the specs in the service manual which I believe you can find somewhere hear on the forum to download.

Tarzan

1. Pull the plugs and inspect them visually. Find a good plug color reference. If you don't know hoe many miles on those plugs, which you likely do not, just replace them.
2. Do a compression check while at it.
3. Do what AC MAX 92 said.
4. Air filter should be inspected and replaced if old. Maybe just replace the fuel filter as an insurance as well.

zoltan

Thanks for all the help. The check engine light is not flashing and the oil leak seems very minimal, I will try to check out the cam and crank sensors, and the resistance on each coil as well. Fuel and air and plugs are new.

CMax03

iTrader: (3)

You can use an ole school timing light to identify any missing as well....place inductive pick up around coil pack harness wiring!

Tarzan

No, that won't work, as the 'ole school timing light' only works from high voltage of the 'ole school' ignition wires.

CMax03

iTrader: (3)

Really? Are you crazy? So how does the DYNO shop hook it up? With an Inductive timing pickup around your #1 coilpack harness! I've been doing this since 1995 since the 4th Gen hit the streets and I quess I've been hallucinating for 20 yrs+....It's a good way to see how each coilpack is firing! Consistent or erratic! Don't be a Nay Sayer try it! It works.....

Tarzan

Are we talking about the same thing? By the 'old school' timing light I understand the fluorescent light, which clamps to the ignition wire. Is yours different? I don't do this style of timing for 12+ years, so not following any progress in this area.

CMax03

iTrader: (3)

WTF did a fluorescent come from? I'm speaking of an Pistol type strobe timing light being used to look at crank timing and verify that the coilpack are firing consistently...If I have to I'll make a youtube video...Since you don't know this works...

Tarzan

Okay, time to terminate conversations with you, as you have no understanding of the basics of electric circuits and components, but make far reaching accusations and assumptions. I built those timing guns from components back in the day, so I know what I am talking about. Off to ignore list you go.

CMax03

iTrader: (3)

I'll make you a Youtube video then....