johnnyv1986

Hello everyone. My brother recently bought himself a 1997 Grand Cherokee. It ran good on when we went and looked at it. Drove it down the back alley and no problems. Started it and shut if off a couple of times and no problems. Drove it home (about 5km) with no issues either. Once we got it home, I took and changed the spark plugs to NGK copper's, replaced the cap and rotor and replaced the plug wires. Ever since then we have had nothing but problems with it stalling or not starting. Oh and he replaced the battery as well.

We got it to a shop, died over 6 times driving it there (about 10km). They took and fixed the pickup coil connector. They said it ran fine for them, no problems. My brother picked it up and drove it home and it died on him twice while pulling into the garage. Now this morning we can't get it to start at all. We took and replaced the coil and still no luck. I don't know what else to do. It will cost over $100 to get it towed to the shop and have them look at it since they didn't fix the problem. I tried wiggling the connectors and still nothing. While trying to get it to start, I did get a very loud bang out the exhaust, I'm guessing it was flooded.

The vehicle has 224,700 miles on it and is 2wd and automatic. Has power windows and power locks and air conditioning.

Any ideas of suggestions? It's suppose to get down to -20 to -30 in a couple days and he needs to get this thing running. Thank you for your help!

I should also mention that if I hook my scanner up to the jeep I get a code for the primary ignition coil circuit, but I don't have a check engine light on when it actually does run. I tried deleting the code with the scanner but it says it can't connect so it can't delete the code.

*Update* I just took and pulled all the new plugs and they were wet, so I took and put the old ones back in since they were working.... Again, it didn't start, I tried 3 times. I pulled one of the plugs after and it was wet with fuel. So It looks like it is a spark issue.....

dave1123

The quickest and cheapest thing you can do is replace the coil.

Bustedback

Replace the crank sensor.

johnnyv1986

We did take and return the coil and exchange it and got it installed. Still nothing.

We are going to try checking the crank sensor and see if that helps. Thanks everyone for the the help and I'll let you know if it fixes the problem.

johnnyv1986

Good morning everyone. So I took and snapped a couple pictures for you to look at... I pulled the connector for the CPS apart and put it back together, thinking maybe a bad connection. Tried to turn it over, it started for about 10 seconds and then died. I had a look at the CPS from the driver side of the engine and it is looking quite clean, so I am guessing it has been replaced. Looking at the connector... the one from the harness is quite dirty but the one from the CPS is looking clean. I also double checked the plugs we had bought and they are Champion RC12LYC plugs. The ones that I reinstalled (the old ones) are Autolite double platinum. Hopefully this is the problem. My brother is calling the shop tomorrow as they will have to either come here or have it towed to them since they charged us saying it was fixed but it isn't. Told him to have them replace the CPS with a Mopar branded one and to replace the plugs with the ones we bought.

97grand4.0

Usual suspects are the crank position sensor, and the cam position sensor, aka distributor switchplate. Shooting in the wind here but since you mention you did the cap and rotor, the switchplate would be worth a look. Since the code is for ignition, I would disconnect the harness from the coil and probe it with a voltmeter for +12vdc with the key on engine off. Ground the negative probe of the meter and dont short across both terminals on the harness, just carefully probe each one. One of the two should have plus 12.

dave1123

Just a point with me, get rid of the Fram filter. They use cardboard end plates on the filter element.

CPS? Go Mopar and stop worrying. When you get it out, check the magnetic strength between the old one and the new one. The CPS is a Hall-effect switch that senses objects near it by the changes in the magnetic field.

When I changed mine, I found the easiest way to get to it was to drop the transmission crossmember and lower the transmission down. Just take out the bolts in the frame and leave it attached to the trans.

johnnyv1986

Sorry about the delay in my response/update. My brother ended up having the shop tow it to them. It ran fine that first day, it actually started after the tow truck dropped it off. The next day it started acting up.

Turns out the ECM is on it's way out. Now he is waiting for them to get one. The shop said that there is only 1 available in Alberta so going to try looking elsewhere.

Once they get it replaced I will let you know if it works or not. Thank you everyone for your very helpful ideas and suggestions.

Yes, personally I don't like FRAM either but the oil was just changed so on the next oil change I am going to have it replaced with a better filter.

dave1123

There are several interesting videos on YouTube where they cut open several brands to show what's inside. What I found amusing is most of them have a 30 micron filter media and being a hydraulics guy, that's a screen door to me!

spartan762

I had a very similar issue with my 94. I replaced the CPS and ignition coil,that seemed to do the trick. Anyhow be careful which computer you get. Not all PCM's are compatible, depending the year. Some companies only sell rebuilt/refurbished parts. Lots of mixed reviews on refurbished/ new/dealer parts. Rockauto.com and partsgeek.com ain't too shabby

johnnyv1986

*UPDATE* The shop got it running. Got a used computer for around $180 plus $50 shipping. I think he said total bill was around $500 with the computer/ship and they used 1/2 tank of his fuel. Told them to also clean the grounds and tan/black wire pcm ground. So far so good, doesn't seem to have anymore problems with it running.

He also was finally able to get his winter tires installed on it. Now just have to figure out why the interior lights stay on. I was looking in the fuse panel because the interior lights weren't working. Put a fuse in and then they just stayed on so I pulled the fuse again. Oh and I've also got to look into why the back window won't lock when the vehicle is locked.

Anyways, thank you everyone for all the help!

97grand4.0

The dreaded 'I paid someone else to diagnose and fix it.'
Let us know how that works out.

The lights stay on because
The switch on the back of either or both of the front door lock cylinders is stuck in the unlock position.
The switch that senses the rear hatch is rusted out in the unlock position.
Also the rear glass unlock...tons of problems on the 97 with all those.
If the alarm wont set also that is sure the prob.