Howdy folks,

This post is for new owners of used CRDs who may learn from my initial trials with an otherwise great Jeep. I bought a used 2006 Liberty 2.8 CRD and the first thing I looked at doing past an oil change and K&N filter swap was the glow plugs - I had heard about the tendency of the Bosch ceramic ones breaking. The engine light was on so I pulled the codes and ended up with the four in the subject line. For those that don't know, these are codes indicating voltage inconsistency to the glow plugs - and each code indicates the respective cylinder (P1261 = cyl. one, P1263 = cyl. 2, P1265 = cyl. 3, P1267 = cyl. 4). Having bought this truck used I suspected the wrong plugs as I also knew some trucks had been converted by the dealer away from the stock 7V system to a 5V system (dealer can often trace the upgrade if it is performed - I was fortunate the truck was one owner as the dealers maintain records specific to the repairs or modifications they made and not all authorized dealers, surprisingly). I quickly found out how hidden the glow plugs are - removal of the alternator bracket is necessary to reach cylinders 1 and 2, removal of the EGR pipe for cylinders 3 and 4 (note that the gasket for the pipe as it mates up to the intake is P/N 05066946AA and still available online for around $20 after shipping - noticed some folks using RTV but I chose to order it for cleaner removal down the road.) I also learned that the plug in cylinder 1 was a 5v Bosch plug with a red band around the back (not that you could easily see such band anyhow - the plug is stamped after you remove it and easily readable). I ordered some 7v Etechno1 plugs (steel) to replace the old ones which turned out to be in surprisingly good condition on cylinders 1 and 2 (I found out why later and here's where it gets interesting to other noob CRD owners with these codes). Replacement of the plugs in 1 and 2 eliminated codes P1261 and P1263 - leaving only the faults in the two rear cylinders ... the clear conclusion was that the previous owner had replaced the plugs with the incorrect 5v Bosch ceramic ones, causing a low voltage condition to its respective controller. If other new owners have all four codes and no others showing, there may be a strong likelihood that the wrong ones were installed as they are apparently more readily available in hot climates such as Texas where I live. Hope this helps someone else and its great to be a member of such a useful forum for this great and somewhat uncommon Jeep!

Cheers

Your conclusion is a little off. The glowplug doesn't dictate the voltage. The ecm does, hence the 5volt reflash some have. I can speak of this because I am running 5 volt plugs on 7 volt tuning. The plugs get hotter and help in the winter months

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2005 Crd Silver Limited- arps, rockers, 7v etechno's, egr deleted, v6 airbox, metal cac's. Yeti's stage 2 tune. Euro TC, Ram tcm, pml transmission pan, facet lift pump

Thanks for the reply, I probably mis-spoke....I did mean the same thing as what you indicated, that the ECM dictates the voltage...in my case having 5 volt plugs where 7v ones are expected, which gives the 'high to low side short' condition in all cylinders. Needless to say reprogramming of the ECM to 5v that some Jeep dealers did changes that scenario. As hot as it is here, I can't see the glow plugs ever attempting to heat up but 1-2 months a year anyhow (wish I could throw em out completely, woulda saved $100 on a set of four steel 7v ones lol)! Thanks again for the reply, apologies if it seemed unclear...just passing along my observations Happy Jeepin!

How have people been making out running the 5 volt glow plugs with the 7 volt tune?

What are the best 5 volt glow plugs to buy these days?

I have been running 5 volt glow plugs on the 7 volt tune ever since the Jeep has been runninng

I just got code P1267

I also got a new code P1251 - could they be related?

I do not notice any starting or driving issues

It seemed I did hear an odd noise - seemed like it was coming from the back of the Jeep when I turned the key to run to check codes

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2006 Jeep Liberty CRD 142,000 miles New engine 2-2014, Green Eco tune, FS2500 bypass filter Weeks elbow, European Torque converter, brakes front UCA's wheel bearing and front hubs. Front hitch OEM lift pump
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