Jeep won't start- In need of help

[jsreichard]

This may be long and I apologize in advance. I have a 1995 Jeep Wrangler 2.5L, standard. This summer we replaced the ECM with a used one. We also replaced the distributor cap and rotor, coil, spark plugs, and fuel pump relay. It ran fine until it got cold. The check engine still comes on when we try to start so if I am correct from the many searches online I did, then that should mean it isn't the ECM again. The Jeep was very hard to start and would start then stall several times before staying running. when it was warmer it would start with no problem. If it wasn't let warm up then it would buck and jerk. If it was warm before we left it would run fine. Through my many searches I decide that perhaps it sounded like the Crank Position Sensor so last night my husband changed it. The Jeep would not start at all, so he changed it back and now it still won't start. We are at our wits end and need some help. he checked for spark last night and he doesn't have any. Does anyone have any ideas. This is our only vehicle and tommorw as everyone knows is Christmas. We are desperate to try and figure this out. Thank you very much!

 

[socal_dave]

Have you pulled the codes from the check engine light or hooked up and odb2 reader?

when your check engine light is coming on, there's generally a procedure for finding out why. If you're odb2 then you'll need to plug an electronic reader into it, sometimes auto parts stores will loan these out for you.

 

[84cjseven]

I would check out the wires going to the CPS and the plug. And try another sensor. I have seen a lot of these things go bad and new ones not work properly.

 

[IrishMike]

I can only tell you what I would do. I have a 95 wrangler 2.5L standard shift. You have replaced the obvious items but are you getting fuel to the injectors. If it cranks as you stated I would also check the fuel delivery and for dirty injectors as to rough idle and stalling. I went through a problem with the ECM on mine. Do you know there is a different ECM for auto versus standard trannies. I replaced after mine developed a time delay in the autoshutdown fuse. It would start after I turned ignition to on and waited for a minute and heard a click sound. The engine then turned over and ran fine. Hope this can help.

 

[carnuck]

How about the coolant sensor? When they stick 1/2 way, motors can start fine cold, but not when warm or vice versa.

 

[jsreichard]

Ok, well we figured out why it wouldn't start. Is everyone ready for a laugh? He put the sensor on upside down. Now it starts, but we are still having problems. It is very hard to start in the morning or after it has been sitting awhile. When he goes to start it it chugs when he turns the key over, but doesn't actually start. After he turns it over maybe 20 to 50 times it will start, but almost always shuts right back off. He will have to turn it over again several times and then it will finally start and stay running. He has to let it warm up for several minutes. A lot of times after he has let it warmed up it bucks and jerks when he drives it. We had a mechanic look at it (he was the one who found the upside down sensor) put it on a computer and says now he thinks it is the distributor. What do you guys think?

 

[SteelHeadz]

LOL, that's funny. Is the fuel pressure within spec?, timing is okay?. My approach on that situation is to hook up a lab scope and monitor the ignition system to verify signals and their intensity. If there was any intermittent signal failure, the lab scope will pick it up. A hard start in the morning could be due to a weak fuel pump along with the chugging or jerking. The fact that it changes symptoms, makes me think that the issue would be more so in the T.body. Dirty IAC port and t. body plate.

 

[Saddle Tramp]

LOL, that's funny. Is the fuel pressure within spec?, timing is okay?. My approach on that situation is to hook up a lab scope and monitor the ignition system to verify signals and their intensity. If there was any intermittent signal failure, the lab scope will pick it up. A hard start in the morning could be due to a weak fuel pump along with the chugging or jerking. The fact that it changes symptoms, makes me think that the issue would be more so in the T.body. Dirty IAC port and t. body plate.

I'm with SteelHeadz on the failing fuel pump; your symptoms are common to this problem. When cold, the pump doesn’t quite have enough pressure to deliver the gas but once things warm up and expand, you can get by. However at some point the pump will fail and you will be back to not starting at all. I would do a pressure test.

 

[dempsy1]

Sounds like a fuel delivery problem to me also---I had a truck that would start and run great in park or neutral but no go in drive--was weak fuel pump----Had a friend his Jeep was hard to start and his distributator was not in right.

 

[carnuck]

Try turning the key on twice before even turning it over. If that works, the fuel pump relay may be going bad or there is ice/water in the TPS.

 

[Weylyn]

Sounds like your loosing fuel pressure. Cranking that much, your having to bring fuel up the line. As for the bucking, still does not sound like good fuel pressure. Distributer, its possible but I would check fuel first

 

[jsreichard]

Thank you everyone for the advice. i will tell my husband. How do we test the fuel pressure? Is this something we can do ourselves? Would a bad fuel pump make it backfire? It backfired so bad the other day it blew a huge hole in the muffler and sounded like a bomb. Between that happening at 11:30 pm and my husband trying to start the Jeep at 4:30 am and all of the chugging, backfiring and now being loud because of the huge hole in the muffler we are our neighbors most popular people right now. LOL! My husband is so frustrated he wants to either sell of trade the Jeep in, but I want it fixed because I LOVE our Jeep! It is our only car and he has gotten into some major trouble at work because of being late and missing work due to it not starting. We are on a very, very tight budget and all of these repairs are killing us. The Jeep has also now started shutting off while he is driving. He then has problems getting it restarted just like when he first starts it in the morning. It no longer matters how longer lets it warm up, it just acts up the whole time. I really appreciate all of the help. Thanks.

 

[volaredon]

yup. sounds like fuel delivery issue.

 

[tp=n=yj]

The temp sensor is it. When it is cold the gas mix is wrong til engine warms up.the ecm controls gas mix pur temp senser .witch is tell it.s warm. After replacing the $25. Switch the codes will have to be reset or started and warm up from cold around 80 times

 

[jsreichard]

We have driven the Jeep much more than 80 times since replacing the ECM. Also when the mechanic put the computer on the Jeep and they installed a new stator and flipped the crank position sensor around the right way, he wiped the codes and they immediately came right back. I don't remember all of the codes, but one was in reference to the battery having been unplugged and another was something about the air conditioner, which our Jeep does not have air conditioning, and the other 2 were in reference to stator. My husband drove the Jeep to work yesterday and the 30 minute drive took him well over an hour because the Jeep kept shutting off. On the way home from work it shut off more than 20 times and finally shut off and refused to restart. He had to call our bro-in-law and once again have it towed to the mechanic. My husband was able to buy the new distributor and that will be installed tomorrow. I guess we will go from there. I think if the distributor does not help I am going to insist that it has to be something in the fuel system. Wish us luck. Thanks.

 

[Weylyn]

Best of luck Jen, keep us posted.

 

[volaredon]

new stator? you need to pull the alternator apart to change that one. Most people just replace the alternator. Do you mean STARTER?

 

[tp=n=yj]

but did you change the temperature senser before resetting codes or heating up from cold. abou 80 times. the senser tells ecm to change gas mixture.to give more gas or less as the motor gets cold to warmer change senser first then reset

 

[jsreichard]

Sorry it took me so long to get back to everyone. It took quite awhile and a lot of things got changed, but it was the computer, again. This time we sent away for a rebuilt one with a life time warranty. I hope that is the last we will have to deal with that. Now today we have a new problem. It shut off while my husband was driving it and won't restart. He said all the lights went dim and it just shut off. He is thinking alternator, what do you guys say? He tried to restart it and it just clicks. They tried to jump it and nothing. Thanks everyone for all of your help. I really hope I can get my baby back on the road again. It took us off and on 3 months to figure out what was wrong the first time and a lot of money changing this and that. hope this fix will be alot easier.

 

[Operation 4x4]

Sorry it took me so long to get back to everyone. It took quite awhile and a lot of things got changed, but it was the computer, again. This time we sent away for a rebuilt one with a life time warranty. I hope that is the last we will have to deal with that. Now today we have a new problem. It shut off while my husband was driving it and won't restart. He said all the lights went dim and it just shut off. He is thinking alternator, what do you guys say? He tried to restart it and it just clicks. They tried to jump it and nothing. Thanks everyone for all of your help. I really hope I can get my baby back on the road again. It took us off and on 3 months to figure out what was wrong the first time and a lot of money changing this and that. hope this fix will be alot easier.

Sounds like its time for a new alternator. If youe jeep shuts off on you mid-ride its not the battery. A good way to test this is to attach jumper cables to the battery and then grab the other side of the cables and lightly touch them together. If it sparks, then the battery has power and its more than likely your alternator. If it doesnt spark, then your battery is basically dead. Another way is to jump the jeep and then take off the jumper cables. If it shuts off or you notice a loss im power then its your alternator. You may want to also try "push starting" the jeep. Get it on level surface, put the jeep in 2nd gear and hold the clutch down. Have someone (two or three people) push the jeep, once you get enough speed just let go of the clutch. The jeep should turn on. See if you can get any information from that. Hope this helps.

All the best,
Chriss