02 7.3 power stroke hard/no start cold
 

hi, I have a 2002 F-350 with the 7.3. the truck willk not start below 50 degrees if not plugged in. if i plug the truck in over night it starts up no problme. if it is plugged in roughly an hour before i want to start it in mild temps it starts but skips until i drive it and spool the turbo, leading me to belive a couple cylinders are becoming fluded, the truck also smokes profusly upon startup until spolled and brought to a smooth idel. i tested the glow plugs and found two bad ones, and a bad glow plug relay. i replaced all 8 gloplugs with autolite plugs, under v/c harnesses with delphi harnesses, v/c gaskets with ford gaskets, and glowplug relay. i retested the whole system and all checks out perfectly. truck still does not start well/ no difference. i have load tested both battrys indvidually and both checked out exceptionally, and are only 1 year old. i cleaned battry terminals as well. i did a starter draw test and found everything to be well within spec. also tested resistance in starter wire, 0 oms. the truck is bone stock and has 365K on it original engine and has tones of power once running, turbo works flawlessly. i also checked current from battry to gp relay and found 12+ volts. i previously had a 96 f-350 with a 7.3 and never had a problme with it starting, even started in -20 degree weather off glow plugs multipul times as temps drop that low often in northern Maine, i never used the block warmer on that truck (it didnt work). I am strongly considering an injector problme with this truck, when replacing the glow plugs i noticed two injectors have been replaced befoer. This truck is driving me nuts and killing my electric bill, any help would be greatly appriciated, Thanks.

check your valve cover harness, make sure its plugged in good and snug, just double check everything you messed with, its so easy to skip something or not get it plugged all the way in when your working on something anxious to get it done, do that then post back up and let know what you figured out :c:

:welcome: to the site

yea i have double checked everything, and did once again yesterday. everyhing is plugged in and i also tested the glowplugs and for power to all 8 everything is copisetic. im fairly certant the truck is fluding out on a few cylinders, and am suspect of the injectors. im wondering if anyone else has experienced this kind of issue due to injectors before i go dumping a bunch of money into new (upgraded of corse) injectors.

is the truck throwing any trouble codes?

Do a compression check...

Also, check to insure the GPR is turning on when you turn the key on. Use a test light and just make sure!

no trouble codes. and yea gpr is coming on and even if i cross it it still makes no diffrence.

Sounds like you have an injector issue or compression issue.

i am haveing simmiler problems with my 2000 7.3 however i only have 50k on mine owned since new no problems firein up other then new crank sensors till they got that right.
same problem with my fatherinlaws 7.3 it got cold and they done want to start u can crank and crank wait 10 min and crank and sometimes get it started and it will start fine the rest of the day?
if i plug it in fires right up?
we dont buy fuel at the same place
and dred takeing it back to the dealer to hear the gloom and doom

Glow plugs... You need to check your glow plug relay.

GONNA try that tommorow and see how she goes

sorry for so long sence my last post. i have trippl checked everything in the gpsystum everything is functioning perfectly. if i leave the truck for 5-6 hours in 20 degree weather it wil start but skip real bad until it warms up. it acts like it has a couple loaded cylinders, im thinking that i have some bad injector o rings that when they get cold contract and leak by filling the cylinders with oil, my next test rrior to changing the o rings is a compression chec but the truck has tons of balls so it really seems un likely. do the injector o rings make sence? i have delt with a lot of 7.3s but have never come across this problme...

MINE was the short relay selonoid on the top of the motor thanks for the help

You will not get oil into the cylinders with bad o rings...

How many miles on the truck?

my2000 f250 does the same thing. it will not crank unless you have it plugged up over night. but how can a relay cause the problem when it is cold? seems like to me if a relay is bad the truck shouldnt crank no matter what the temp is, my truck only has 150k on it.

might be glow plugs

I have been having the same problems my truck has good compression and new gp and harness as well as relays and even new injectors but still have same exact symptoms as the first post but I also noticed my truck also do not have the factory cold high idle but the ebb valve does work I think it may me a sensor or something that doesn't tell computer it is cold

with the glow plug relay out it will start in warm weather as you do not need them but in cold weather you do hence the no start. plugging in the block heater would make it start. just to be clear i'm only explaining this to him i'm not suggesting something you have said so many times. now are you getting any codes?

Mine will start with reg oil, but much much easier with synthetic oil. Take some 15w 40 and some 5w 40 leave it out over night and see which flows faster. Then you know why the truck chugs when cold if you run 15 40. Mine would crank slow and romp when I had 146 40 in it even if it was 30 degrees. Then I went back to synthetic. I can start it at 0 degrees not plugged in and its just fine. This could help your romps, but has no effect on a no crank, thats another problem

Living in Orlando, Fla. I do not have the 20 degree weather, but I do still ahve the warm up issue. 2003 7.3 236k. Runs and starts just fine the rest of the day. First start in the A.M. is always rough. Like it is only running on 6 cyl. Smooths right out after the engine warms up. Always have given it 10 minuntes in the driveway before going down the highway. "short solonoid"? Is this near the fuel bowl where the 2 solonoids are mounted. One is taller than the other. So you changed out the short one and this fixed your problem?

Glow plug realy

Is that relay the "short one" next to the fuel bowl?:tu:

passenger side of motor, 2nd relay, the one more towards the turbo.

Thanks for the reply. I will check on pricing and get that one changed out!

Does anyone know what the compression should read on these? Our 02 f250 is doing the same thing and has since I put a used engine in it. I have replaced the glow plugs and harness with new vc gaskets, tested the relay and checked the power drain to the glow plugs to make sure they were heating. It will not start cold but will when pluged in. I tested the compression but haven't been able to find out what it is supposed to be. The old engine with 1 bad cylinder and a bad hpop started better than the used engine and I used the injectors from the engine I pulled out so my guess is compression with ours.

Anything below 300 is low... 425 is new or very new...

2002 7.3 hard to start when not plugged into block heater
 

Hey there. I also have the 2002 F350 SD CC X Bed 4x4. Mine has ~185K on it right now. Mine also just noticeably started being hard to start when it's 40 deg or below without being plugged into the heater. I researched and read a lot of material and things seem to indicate the Glow Plug relay. So I called the dealership where I live, told them the situation and dropped it off for diagnosis. They said in my case it was not the relay but it was both glow plug relay harness faulting; therefore not sending enough voltage to 5 of the 8 plugs. They changed all 8 plugs and both harnesses and I left out of there $600 lighter in my pocket, but the issue is now resolved in my case.

Ouch! $600.00. At least I know what my services are worth!!LOL. I have changed out both relays(there are 2 ya know), all 8 glow plugs, with new harnesses, and I had a mechanic shop change out 2 of the injectors that did not "buzz" test properly. With now 332,332.0 miles on my truck I am still using 6 original injectors(I know, should've changed them out long ago!). It is starting to get cool(Florida=hot!)and it is time to use the block heater again! Works like a champ always! Love my 7.3!!