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-   -   95 YJ no spark please see picture !! (http://www.wranglerforum.com/f218/95-yj-no-spark-please-see-picture-145491.html)

Z131 03-10-2012 03:53 PM

95 YJ no spark please see picture !!
 
2 Attachment(s)
I got this jeep, its a 95 and I put a 92 Jeep engine in it, I used the 92 Jeep computer as well. now it wont start. no spark at all. can some one identify this wire, could it be causing the problem ?

DirtyRob 03-10-2012 03:58 PM

That looks like the ecm communication terminal. I may be wrong (and probably am) but that is what it looks like in the pic.

Z131 03-10-2012 04:01 PM

I looked every where and cant find another plug like it. I bought this jeep with no engine and bought the engine and the wire harness.

Jeep716 03-10-2012 04:13 PM

I think that is a factory test plug for use with a old scan tool.

Z131 03-10-2012 08:07 PM

I went to the store today and found a jeep parked, asked the owner and was a 4 Cylinder 94. Apparently there is a relay that plugs in there. I bought the relay, installed it and still no spark !!!!!!!!!!!!!!!!! any ideas ????

Jeep716 03-11-2012 12:00 AM

I wold start testing for power to coil. Is crank sensor plugged in? May have bad grounds as well. Good luck.

Dutch 95 03-11-2012 12:25 AM

Did you only change the engine and no wiring? The first thing I'd suspect is that the 92 computer is trying to run a 95 engine, and (likely can't). Because of wiring/sensor changes throughout the years, one wire might make the difference. If you only added the engine itself, I'd put the 95 computer back in. Can't hurt.

Frenz 03-11-2012 12:49 AM

What ECU are you running.. the 828 symptoms are spark and or fuel.

Xpress 03-11-2012 09:08 AM

I believe the ECM's from 1992 and 1995 are the same.. Don't quote me on that though.

Did you replace the crank sensor with the correct sensor? I know somewhere in the 2.5L years they changed the flywheel to a different one that will not work with certain newer year components. How about using the correct MAF? The relays all plugged in? TPS is the correct unit?

Dutch 95 03-11-2012 10:01 AM

Nope they aren't the same part number. I'd try putting it back in.

Z131 03-11-2012 10:45 AM

Quote:

Originally Posted by Dutch 95 (Post 2127116)
Did you only change the engine and no wiring? The first thing I'd suspect is that the 92 computer is trying to run a 95 engine, and (likely can't). Because of wiring/sensor changes throughout the years, one wire might make the difference. If you only added the engine itself, I'd put the 95 computer back in. Can't hurt.

I have two computes, the 95 and the 92 and both didn't work, I used the wiring off the 92 I don't have any loose plugs now, everything is plugged in correct

Z131 03-11-2012 10:48 AM

Quote:

Originally Posted by Xpress (Post 2127501)
I believe the ECM's from 1992 and 1995 are the same.. Don't quote me on that though.

Did you replace the crank sensor with the correct sensor? I know somewhere in the 2.5L years they changed the flywheel to a different one that will not work with certain newer year components. How about using the correct MAF? The relays all plugged in? TPS is the correct unit?

I haven't tried to change the cranksensor but I looked at the interchange and its the same from 91 to 95 where is the MAF located, the one on the firewall ? all relays are in. what is TPS ?

by the way, while I was looking under the dash today, I found an aftermarket alarm system, could that be the issue ? but when I try to start it, the alaram dosent go off at all

Z131 03-11-2012 10:50 AM

Quote:

Originally Posted by Frenz (Post 2127160)
What ECU are you running.. the 828 symptoms are spark and or fuel.

How do I know what ECU ? what you mean 828 ?

Shanman 03-11-2012 11:26 AM

Tps is throttle positioning sensor. It is the sensor right there where your throttle cable hooks to the intake. Maf is mass air flow. It is usually in the air intake right before the intake( if that makes sense). My 94 has map sensor instead of a maf. It is located above the rear of the valve cover mounted on the firewall. It will have an electrical connection and a vac connection

Shanman 03-11-2012 11:27 AM

I would also unhook that alarm system. If it isn't hooked up to the horn, it may be going off and you just can't hear it, keeping it from starting

Garyk 03-11-2012 11:31 AM

Quote:

Originally Posted by Z131 (Post 2127710)
I haven't tried to change the cranksensor but I looked at the interchange and its the same from 91 to 95 where is the MAF located, the one on the firewall ? all relays are in. what is TPS ?

by the way, while I was looking under the dash today, I found an aftermarket alarm system, could that be the issue ? but when I try to start it, the alaram dosent go off at all

I would certainly eliminate the alarm issue....this may be your problem if its Does the engine turn over? Is the fuel pump running? Power at the coil?

93jeepwranglerman 03-11-2012 11:48 AM

Im having the same prob ive bought all new sensors coil packs distrobuter and I only get fire after I let off the switch

Dutch 95 03-11-2012 12:16 PM

Our Jeeps don't have a MAF (mass air flow sensor). They have a MAP (manifold air pressure sensor) and a MAT (manifold air temperature sensor). Have you checked for spark at the ignition module? Is the ignition module plugged in, it should have the coil wire on the left side and a connector from harness on the right side.

Z131 03-11-2012 09:19 PM

Quote:

Originally Posted by Dutch 95 (Post 2127944)
Our Jeeps don't have a MAF (mass air flow sensor). They have a MAP (manifold air pressure sensor) and a MAT (manifold air temperature sensor). Have you checked for spark at the ignition module? Is the ignition module plugged in, it should have the coil wire on the left side and a connector from harness on the right side.

there is a MAP sensor plugged on the firewall, How do I check for Spark ?? I suppose I have to have some one turn the car over while I pull the coil wire ? fuel pump is running good, I even checked the fuel pressure and its good, would the TPS prevent it from starting ? I need to check if its good too. I'll start by removing the alarm system first and see.

Z131 03-11-2012 09:20 PM

Quote:

Originally Posted by 93jeepwranglerman (Post 2127868)
Im having the same prob ive bought all new sensors coil packs distrobuter and I only get fire after I let off the switch

Did you check the computer ??

Dutch 95 03-11-2012 10:49 PM

No the MAP won't effect the spark.

Is your Jeep a manual or automatic? The method for checking the ignition module is different from one to the other.

Z131 03-11-2012 11:03 PM

Its a manual

STUUPID 03-12-2012 07:47 AM

The connector in the picture i do believe is for an AC harness. I purchased my 94 in 95 an that connector has never been used for anything. The diagnostic connector for the ECM is a little pigtail by the ECM connector. Your 92 engine may have used a different style injector system than the 95. The fuel rail is different and the injectors may be as well. Does the fuel relay kick on? Is the ASD relay turning everything off? Check to see with key on, if you have power to your coil and injectors to start off with.

Z131 03-13-2012 07:54 PM

there is power goin to the coil, ground and positive but no spark goin out of the coil, I tried to change the coil and no luck, what next to check ?

STUUPID 03-14-2012 09:32 AM

Check to see if the distributor is giving signal to the coil to fire. use a test light with key on, check that you have constant power to one side. go to signal wire next and have someone turn jeep over while watching light. Light should pulse. If it does not, make sure you have proper voltage to the cam sensor in your distributor and crank sensor and both of those are working.

Z131 03-14-2012 04:33 PM

Quote:

Originally Posted by STUUPID (Post 2139063)
Check to see if the distributor is giving signal to the coil to fire. use a test light with key on, check that you have constant power to one side. go to signal wire next and have someone turn jeep over while watching light. Light should pulse. If it does not, make sure you have proper voltage to the cam sensor in your distributor and crank sensor and both of those are working.

No plus or constant power out of the distributor, does these even have a cam sensor ?? What to do next ? I opened the distrubutor and it's looks clean, nothing out of the ordinary !!

STUUPID 03-15-2012 06:48 AM

You should have constant power TO one side of the coil with key on. You should have a constant 8 volts TO distributor with key on. The cam sensor is inside the distributor. If you have access to a manual it should tell you how to test it. If not, do a forum search under yj forum. Should find your answer there. I understand how frustrating this can be. I have an electrical issue with mine that has left it sitting for 3 months that I can't seem to find.:banghead:

Z131 03-15-2012 09:49 AM

Quote:

Originally Posted by STUUPID (Post 2142392)
You should have constant power TO one side of the coil with key on. You should have a constant 8 volts TO distributor with key on. The cam sensor is inside the distributor. If you have access to a manual it should tell you how to test it. If not, do a forum search under yj forum. Should find your answer there. I understand how frustrating this can be. I have an electrical issue with mine that has left it sitting for 3 months that I can't seem to find.:banghead:

Thank you so much man !! I found a write up on how to test it, I'll try it now, It really sucks cause the weather is nice and I can't drive it. what kind of issue you have with yours ?

Dr Doug 03-15-2012 03:34 PM

Have similar problem
 
Quote:

Originally Posted by Z131 (Post 2142837)
Thank you so much man !! I found a write up on how to test it, I'll try it now, It really sucks cause the weather is nice and I can't drive it. what kind of issue you have with yours ?

The crankshaft position sensor needs to be changed. It may look brand new but no good. It's a good investment especially if there are any questions. I had a no start condition as well and when we changed the CPS it started right up.

Some other things to check:
1. when you turn on the key you should hear the fuel pump come on and may hear a click or two from the relay in the power distribution center (just forward of the battery). If you do not hear this then your PCM (powertrain control Module)may be bad and/or your fuel pump relay may be bad.
2. check the fuel pump relay. This is very easy - just switch the fuel pump relay with another working relay (e.g., the horn - just make sure the horn relay works first by sounding the horn).
3. You can also check to make sure you have some pressure in the fuel rail by depressing the test port pressure fitting on the fuel rail (it looks like the air valve for a tire on the fuel rail by towards the front). Depress the fitting a small amount of gas should gush out (you may want to put a paper towl on the manifold to absorb the gas).
3. Check the coil. Is it new? This is another good investment if you are not sure about the coil quality. ALso, if you been messing with cranking and cranking and cranking without having the ignition wire connected to the distributor cap, it could damage the coil.
4. Check the continuity on the double pronged wire going into the coil. This was another problem I had. A no start condition was driving me nuts. I changed the coil and it started right up. but then I could shut it down by jiggling the coil wire. I'm replacing it.

Regarding your connector in the picture. It is definitly not the PCM connnector. That is on the left side by the PCM (computer).

crutch 03-16-2012 12:41 PM

I would say it could be the cam sensor in the dist. or the crank sensor on the top of the bell housing. if you have an OBDII reader it will tell you if either one of the are the culprit. At least it worked that way on my 95


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