What was done to YOUR rig(XJ/MJ) today MECHANICALY????

[IslanderOffRoad]

Was the jeep hot or cold?

 

[sandsgg]

Hot Fresh off Of A 75 Mph Run. Then A Quick Trip Across The Street To The Store. Came Out Didn't Want To Start, Got It Running drove Half A Mile And She Died In The Street While Still Accelerating

 

[IslanderOffRoad]

Bet you it starts this am now that it's cold

If so definitely cps

 

[sandsgg]

Still Won't Start I Love My Mj But I Need Her To run :bawl:

 

[Ecomike]

Bad CPS, rotor & cap, leaking fuel pressure regulator (into the vacuum line), bad MAT temp sensor in the intake manifold and bad grounds are the only no start causes I have ever had.

But that back fire usually means a MAP vacuum line leak, so I would test the MAP sensor itself, volt or ohm meter.

If the CPS is a recent aftermarket one it may have a bad wire connection inside the sensor. It is getting COMMON!!! I bought my last good ones from Rock Auto, got the Standard brand made in Italy (not in china) and they are working great. Have you tested the AC output voltage while cranking, of the CPS? Needs to be at least 0.50 AC (not DC) Volts!!!

 

[sandsgg]

I Havent Had A Chance, Yet, When It Did That Backfire It Shot The Vac Hose From My Air Filter To The Intake off

 

[sandsgg]

The Only Problem I See With It Being The Map Is That The Vac Line From It To The Tb Is Pristine still

 

[Ecomike]

The Only Problem I See With It Being The Map Is That The Vac Line From It To The Tb Is Pristine still

Only time I had a back fire was when the MAP sensor put out bad data to the ECU because of a loose vacuum hose. I never have had a bad MAP, but I assume a bad MAP can cause a backfire. Also a bad MAP (I think), or a disconnected MAP can cause a no start!!!!

 

[sandsgg]

how Do I Test The Map Then

 

[Swamprat]

had the same issue, it was a CPS. then i didn't tighten it down enough and spent a fortune before selling the jeep.

 

[Crusher16]

Went and got another socket from NAPA that didn't end up fitting.

Buuutttt the socket in the jeep started working fine again. Problem solved.

Put on a new radiator cap for S n' Gs. Jeep goes a little over 210 now, but the temp doesn't slowly creep higher and higher now. Amazing. Still going to convert to efans within the next month or two.

 

[IslanderOffRoad]

Went and got another socket from NAPA that didn't end up fitting.

Buuutttt the socket in the jeep started working fine again. Problem solved.

Put on a new radiator cap for S n' Gs. Jeep goes a little over 210 now, but the temp doesn't slowly creep higher and higher now. Amazing. Still going to convert to efans within the next month or two.

Why efans? I like the stock mechanical fan

Add a ZJ 4.0 HD fan clutch and you'll never get hot.

 

[Crusher16]

Why efans? I like the stock mechanical fan

Add a ZJ 4.0 HD fan clutch and you'll never get hot.

I figured the 3 efan setup from DirtBound offroad would be a nice setup for when I'm done mall crawling and actually go places.

 

[Ecomike]

how Do I Test The Map Then

http://www.lunghd.com/Tech_Articles/Engine/Basic_Sensors_Diagnostics.htm

Is a great tech write up.

Cruiser54 has a nice Renix sensor testing write up posted all over the internet now, including here on .

 

[Ecomike]

Went and got another socket from NAPA that didn't end up fitting.

Buuutttt the socket in the jeep started working fine again. Problem solved.

Put on a new radiator cap for S n' Gs. Jeep goes a little over 210 now, but the temp doesn't slowly creep higher and higher now. Amazing. Still going to convert to efans within the next month or two.

Make sure you have a large enough alternator to handle the extra power loads first!!!

 

[sandsgg]

So I Replaced The Cps...... Still No Spark. Grabbing A Coil And An Ignition Module From The Jy Tomorrow. Map Didn't Fix It Either

 

[Ecomike]

What CPS source did you use for the replacement?

Did you drill out the holes on the new CPS one drill size larger and push the CPS closer to the flywheel while tightening the bolts?

Is it putting out at least 0.50 AC volts while cranking?

Is the battery holding at least 10 volts while cranking, and is the engine turning fast enough while cranking?

Renix will not start if these are not all there.

 

[sandsgg]

I Used Bwd Which I Have Been Using For Years, My Cps In My 95 Was Bwd, Battery Has plenty Of Juice, Haven't Checked The Cps Measurements Or Drilled It Out Yet

 

[sandsgg]

I May Repair The Old One And Try It As Well

 

[Crusher16]

I figured the 3 efan setup from DirtBound offroad would be a nice setup for when I'm done mall crawling and actually go places.

Just remembered the fact that my current efan doesn't even kick on at higher temps anyways.

Make sure you have a large enough alternator to handle the extra power loads first!!!

Yep. I'll order a 120 amp alternator when I order the fans.