Cold start questions

rescue.tech · **Joined:** Sat Dec 31, 2011 10:55 am **Posts:** 43

So my 05 starts hard during cold weather, unlike my wife's 05 which starts right up like it should. Both of them under the same conditions. It will start in fact has not ever not started even thought I might have to attempt to start it many times, but it will start and run a few cylinders first then the rest will pick up.

I read many of posts here trying to figure it out, plus I am/was a diesel mechanic years ago. But......

What I am looking for is the next route to trouble shoot the glow plug system.

I ohmed the plugs at the relay and the results were:

All plugs went to ground or 0000.0 ohms. From the reading I have do here the plugs should be .5 to 1.5 and anything over 5 they are bad. But I have not found anything to suggest if they are 0 what that would mean. I don't feel they should be 0 but I checked them twice.

So what are my next moves. I would like to trouble shoot the relay and work from there. Before I move on I wanted to make sure the plugs are good still. Plus I was looking for directions to the next part of trouble shooting.

Thanks
Clint

gmctd · **Posted:** Sat Dec 06, 2014 2:41 am

Looks like ur using the wrong ohms range on the DVOM - you should be looking at 0.0000, not 0000.0

If that's a typeaux, then never mind.........................

A manual-ranged DVOM is better for lo-ohms readings than the auto-ranging versions, particularly so if ur not getting a good solid reliable ground connection

An excellent test would be to compare gp resistance values in ur significant other's KJ to ur KJ, side-by-side, noting any difference in values

Then swap the gp modules - they're available on eBay new for ~30bucks from on-line DCJ dealerships

dh100m · **Posted:** Sat Dec 06, 2014 3:07 pm

best way to test if gp plugs are working correctly is with an amp meter find 12v to relay insert
or clamp on meter 100 amp range . measure all or one at a time I have a amp meter in the cabin can check all the time

gmctd · **Posted:** Sat Dec 06, 2014 3:33 pm

dh100m wrote:

best way to test if gp plugs are working correctly is with an amp meter find 12v to relay insert
or clamp on meter 100 amp range . measure all or one at a time I have a amp meter in the cabin can check all the time

The gp's draw ~5a each, 20a total

ArmyChief · **Posted:** Sat Dec 06, 2014 3:54 pm

gmctd wrote:

dh100m wrote:

best way to test if gp plugs are working correctly is with an amp meter find 12v to relay insert
or clamp on meter 100 amp range . measure all or one at a time I have a amp meter in the cabin can check all the time

The gp's draw ~5a each, 20a total

Is that a drags for all three possibilities? (5VDC Ceramic, 5VDC Bosch & 7VDC ECTENO)

gmctd · **Posted:** Sat Dec 06, 2014 5:18 pm

That is for the oem 7v versions - EMT guy didn't mention having other gp's - however, drive current is controlled within the gp module by PWM - 'nuther words, the wider the pulse the greater the available volt\amps

dh100m · **Posted:** Sun Dec 07, 2014 8:13 am

i have not measured 5v plugs but seems to me if they only 5 amps then 5x5=25 watts not much heat there 12x15=180 watts strange that in eroupe they run 12v and not here

Rocky05 · **Joined:** Fri May 17, 2013 11:38 pm **Posts:** 44

dh100m wrote:

i have not measured 5v plugs but seems to me if they only 5 amps then 5x5=25 watts not much heat there 12x15=180 watts strange that in eroupe they run 12v and not here

Ummm? Where did you come up with these numbers????

rescue.tech · **Joined:** Sat Dec 31, 2011 10:55 am **Posts:** 43

Thanks folks, I will give those suggestions a try and get back to ya. Cant do it today I am on the road doing the Pony Express thing for work but will know more hopefully by Thursday.

Thanks again
Clint

dh100m · **Posted:** Sun Dec 07, 2014 12:26 pm

5 volt gp draw 5 amps each 5x5=25 watts 5x7=35 12volt plugs when hot draw 15 amps so
12x15=180watts per each plug

gmctd · **Posted:** Sun Dec 07, 2014 12:39 pm

dh100m wrote:

5 volt gp draw 5 amps each 5x5=25 watts 5x7=35 12volt plugs when hot draw 15 amps so
12x15=180watts per each plug

5 glow plugs? What, do you keep one inside on the seat to keep you warm? We only got four (4), one for each cylinder, eh...........

jws84_02 · **Posted:** Sun Dec 07, 2014 3:42 pm

He's saying 5volt x 5 amps=25 watts

7volt gp's x 5 amps=35 watts

"Bang head"

greiswig · **Posted:** Sun Dec 07, 2014 3:47 pm

dh100m wrote:

5 volt gp draw 5 amps each 5x5=25 watts 5x7=35 12volt plugs when hot draw 15 amps so
12x15=180watts per each plug

Chances are very good the manufacturer changed the R of the filament for different voltages, so they would make roughly the same power. I.e., 12v plugs (if there are any in Europe, and if you know of their use in this engine it would help to elaborate) would likely not draw 5 amps. You are assuming current draw is a constant.

gmctd · **Posted:** Sun Dec 07, 2014 5:59 pm

jws84_02 wrote:

He's saying 5volt x 5 amps=25 watts

7volt gp's x 5 amps=35 watts

"Bang head"

, eh.........

rescue.tech · **Joined:** Sat Dec 31, 2011 10:55 am **Posts:** 43

ok somewhat of an update.

I switched the relays with no change.

I was talking with Kieth from GDE and he said that my jeep has a 5v gp flash from the dealer and the tune I have from him is for 5v. But I have no idea what I have. There is a yellow sticker on the front that says factory ....7v... Other than that I have not seen any indication to which I have.

Is there a way to tell between the plugs without removal of the plugs.

Another question I have is will the flash mean the difference between weather or not they will work. I.e. 7v plugs with a 5v flash.
I have been trying to search for this but couldn't find to much.

I am also foggy as to which is the best plugs to use and what to replace them if I need to.

Thanks in advance.

Clint

rescue.tech · **Joined:** Sat Dec 31, 2011 10:55 am **Posts:** 43

Ok so I am in the process of doing the flow control valve delete and finally ordered some 5v Glow plugs. So I got the plugs out today and 4 of the 4 all ohmed no restance or 0. They all glowed bright red instantly when hooked to the battery. But I ohmed them again and one was ohmed open. So I tried it on the battery again and nothing. This also happens to be the same one that is under the intake or number 3 I think. But anyways it was very difficult to get out from within the hole. Number 4 was not as difficult but came out.

So they are 5v plugs and will see if this makes a difference. Hopefully one plug was the problem, It felt like only two cylinders were firing when it was running when it did start. Maybe the other was on its way out and would not run on 5v but will with 12v.

Wish me luck I am putting in all new.

Clint

thermorex · **Posted:** Fri Jan 09, 2015 9:13 am

rescue.tech wrote:

Ok so I am in the process of doing the flow control valve delete and finally ordered some 5v Glow plugs. So I got the plugs out today and 4 of the 4 all ohmed no restance or 0. They all glowed bright red instantly when hooked to the battery. But I ohmed them again and one was ohmed open. So I tried it on the battery again and nothing. This also happens to be the same one that is under the intake or number 3 I think. But anyways it was very difficult to get out from within the hole. Number 4 was not as difficult but came out.

So they are 5v plugs and will see if this makes a difference. Hopefully one plug was the problem, It felt like only two cylinders were firing when it was running when it did start. Maybe the other was on its way out and would not run on 5v but will with 12v.

Wish me luck I am putting in all new.

Clint

Don't check the 5 v glow plugs on 12v. You'll fry them. If you want to check them, use the harness they are connected to with the relay. Unless you did that and I misunderstood.

dirtmover · **Posted:** Fri Jan 09, 2015 10:35 am

thermorex wrote:

Don't check the 5 v glow plugs on 12v.

Yeah, this was my immediate reaction but when I re-read I think he was testing the old ones and probably did fry #3 but doesn't care since they're destined for the trash anyway.

Going back to the original post I suspect you may be observing the difference between 7V ceramics in your wife's car and the colder 5V plugs in your car. I wouldn't be surprised if your new replacements behave the same.

rescue.tech · **Joined:** Sat Dec 31, 2011 10:55 am **Posts:** 43

Thanks gentlemen, but yea the can they will go.

That will be interesting if that is the case 7 vs 5 volts. I mean tonight it was 0 and hers just popped right off with only the littlest of a miss.

But mine I would have had to start it 6 or 7 times. I mean it would start but really rough like only on two cylinders at first then three and then it pops off and runs good.

So I am curious what was "Jeep" idea about changing to 5v from the 7volts anyway. I missed the whole thing because I got into the game late.

Clint

rescue.tech · **Joined:** Sat Dec 31, 2011 10:55 am **Posts:** 43

Ok so I have the new plugs in and it hasn't been really cold to really test them but I feel they are better now. Coldest I have had to start it in lately is around the 20's and the jeep started decent before the new plugs but now it starts just fine. Kinda hard to really tell the difference between new and old until it gets really cold.

But as to the difference between 5v and 7v. If my wife's are 7v there is definitely and noticeable difference. Hers is much better than mine when it comes to starting.

Also on a side note I did the FCV delete and found that both mine and hers had leaks from the egr tube. Mine was down on the egr where the tube bolts to the egr and was only finger tight. I could hear the air leaking thru it for awhile now and glad I got it fixed because my fuel mileage is back to normal. I have had a oil leak in that area since I bought the jeep two years ago. Glad that is stopped now.

The wife's leak was from under the FCV itself where the v band clamp connects the tube. Hers had a ton of soot up around the fuel filter area. Hers hasn't been leaking as long but here fuel mileage should come back too.

Thanks for all the help and suggestion

Cold start questions

Who is online