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billritter
Active Member

28 Posts

Posted - 08/30/2010 :  10:52:44 AM  Show Profile  Visit billritter's Homepage  Reply with Quote
I have a 1996 t444e. It will start and idle fine, but once you put it in gear and start moving it cuts out and runs very rough. It never dies, it just runs bad. It cannot even be driven out of the parking lot. I have changed the oil and both fuel filters with no change, Except that after I changed the upper filter the bus ran fine for about a day.

It has the following codes, inactive now(I cleared them when I thought the problem was fixed): 144, 224, 335, 143, 622, 615, 313, 233.

This is a head scratcher for me, any ideas?

GPwing
Active Member

Canada
32 Posts

Posted - 08/30/2010 :  6:07:12 PM  Show Profile  Visit GPwing's Homepage  Reply with Quote
Looks to me that you have a cam sensor going bad.

144 CMP Signal noise detected
224 KAM Corrupt
335 ICP unable to build pressure during cranking
143 Wrong number of CMP signal transitions per cam revolution
622 Engine using Field Default rating
615 Programmable Parameter KAM Corrupt fault
313 Engine Oil Pressure below warning level
233 Tachometer buffer is inactive
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billritter
Active Member

28 Posts

Posted - 08/30/2010 :  6:15:33 PM  Show Profile  Visit billritter's Homepage  Reply with Quote
GPwing, thanks for the reply. The cam sensor was changed twice (previous mechanic thought 1st replacement was bad), before the bus landed in my lap. I should have included that in the original post.
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GPwing
Active Member

Canada
32 Posts

Posted - 08/30/2010 :  6:28:04 PM  Show Profile  Visit GPwing's Homepage  Reply with Quote
quote:
Originally posted by billritter

I have changed the oil and both fuel filters with no change, Except that after I changed the upper filter the bus ran fine for about a day



Have you checked fuel pressure??
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billritter
Active Member

28 Posts

Posted - 08/30/2010 :  7:00:18 PM  Show Profile  Visit billritter's Homepage  Reply with Quote
planning on it tomorrow, what should the fuel pressure ratings be?
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GPwing
Active Member

Canada
32 Posts

Posted - 08/30/2010 :  8:11:59 PM  Show Profile  Visit GPwing's Homepage  Reply with Quote
IHC Spec's

High idle with [no load]

Fuel Pressure [Minimum] 20 psi (138 kPa)
Fuel Inlet Restriction Maximum 6 in. Hg. Vacuum (20.261 kPa)

Myself I would like to see 40-65 psi minimum

You say that you changed fuel filter. Did you clean pre-Strainer as well??
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billritter
Active Member

28 Posts

Posted - 09/01/2010 :  5:47:03 PM  Show Profile  Visit billritter's Homepage  Reply with Quote
Does the strainer unscrew from the filter housing? I tried to unscrew it today, and could not budge it. I just don't want to break anything. Fuel pressure is 47 psi. I have determined that the problem goes away when the bus is warm, and it runs good.

Edited by - billritter on 09/01/2010 5:52:47 PM
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mastertech
Advanced Member

274 Posts

Posted - 09/01/2010 :  6:51:22 PM  Show Profile  Visit mastertech's Homepage  Reply with Quote
Is your backpressure valve stuck closed? Is it blowing smoke? Fuel filters dont make them run rough just lose power and injectors will cackle if starved for fuel . Any trouble codes?
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mastertech
Advanced Member

274 Posts

Posted - 09/01/2010 :  6:55:17 PM  Show Profile  Visit mastertech's Homepage  Reply with Quote
OOps sorry I forgot about your codes. Check the cam sensor gap in case the cam is walking around. With code 622 you power will be reduced quite a bit anyways and the 1996 were dogs to begin with.
Is it building boost under power ? How much ? Are the exhaust crossover tubes blown out?

Edited by - mastertech on 09/01/2010 7:16:41 PM
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billritter
Active Member

28 Posts

Posted - 09/01/2010 :  7:01:16 PM  Show Profile  Visit billritter's Homepage  Reply with Quote
quote:
Originally posted by mastertech

Is your backpressure valve stuck closed? Is it blowing smoke? Fuel filters dont make them run rough just lose power and injectors will cackle if starved for fuel . Any trouble codes?



Will check the back pressure valve. The bus has plenty of power after it gets warm. It does cackle quite a bit when it is running rough. It does not smoke at all.
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billritter
Active Member

28 Posts

Posted - 09/02/2010 :  06:04:21 AM  Show Profile  Visit billritter's Homepage  Reply with Quote
OK, the fuel strainer was clean as a whistle. I checked the IPR lock nut and it was a little loose. I tightened it up and the problem still remains.
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stewyk
Active Member

20 Posts

Posted - 09/02/2010 :  6:12:27 PM  Show Profile  Visit stewyk's Homepage  Reply with Quote
Just curios as when you start it up does it take a while to fire or is it quick. Once started does it hammer like hell. Do you have to let idle for 20-30 min before taking off. If you shove the peddle to the floor does it sit there and laugh at you. If any of these problems exist then you need to check the IPR pressure with a 4000psi gauge and compare it to computer PSI. A quick check is start it if you can and see if it drives at takeoff normal. If it does NOT shut it off and unplug the IPRS and test again. If this time it drives ok then plug the IPRS back in and do it again pluged in like the first time. If acts like first time you have 1-8 bad injectors. You need to do this all with the engine cold. Do not drive more than 10ft each time to avoid warming the engine. If you do all this and nothing changes then you need to check the IPR for pressure drop or leaking injector o-rings. Check out the post that says need a shotgun. Let me know if this helps. stewy
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billritter
Active Member

28 Posts

Posted - 09/02/2010 :  6:29:01 PM  Show Profile  Visit billritter's Homepage  Reply with Quote
quote:
Originally posted by stewyk

Just curios as when you start it up does it take a while to fire or is it quick. Once started does it hammer like hell. Do you have to let idle for 20-30 min before taking off. If you shove the peddle to the floor does it sit there and laugh at you. If any of these problems exist then you need to check the IPR pressure with a 4000psi gauge and compare it to computer PSI. A quick check is start it if you can and see if it drives at takeoff normal. If it does NOT shut it off and unplug the IPRS and test again. If this time it drives ok then plug the IPRS back in and do it again pluged in like the first time. If acts like first time you have 1-8 bad injectors. You need to do this all with the engine cold. Do not drive more than 10ft each time to avoid warming the engine. If you do all this and nothing changes then you need to check the IPR for pressure drop or leaking injector o-rings. Check out the post that says need a shotgun. Let me know if this helps. stewy



stewy, I did unplug the IPR and there was no change in the way the engine runs when cold (still bad). One thing that does complicate this diagnosis is that I have to wait until the bus cools off before the symptoms appear.

It does laugh at me when I shove the pedal to the floor.

It does not "hammer like hell"

I do have to let it warm up before I can drive it, but not 30 minutes, more like 10.

It has no problem starting cold or hot. It will fire right up.

It does cackle when it is running bad.
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stewyk
Active Member

20 Posts

Posted - 09/02/2010 :  6:46:40 PM  Show Profile  Visit stewyk's Homepage  Reply with Quote
You need to run a pressure check with a 4000psi gauge and see what you actual pressure is. I will check back in the morning to add more to this topic. Stewy
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stewyk
Active Member

20 Posts

Posted - 09/03/2010 :  08:47:35 AM  Show Profile  Visit stewyk's Homepage  Reply with Quote
Back on the subject, How many miles are on the bus. If you unplug the IRPS and nothing changes but still fires up OK and you can drive it after 10-15 mins of idle time then it sounds like you have injector tips carboned up. Have you checked the oil level in the HPP. It should be 3/4 -1" from top. Does it "search" for idle when started. Long cranking time, having to plug the block heater in even at 90 degs, Pushing the peddle to the floor and not going anywhere, Knocking, hammering, cackling, white smoke, no power cold or warm or both, multiple codes are all symptoms of faulty injectors. You can have one or all the symptoms. I had the same problems as you are on a "99" t444e and six out of eight injectors were carboned to where they were dripping and not spraying. If you need injectors call http://www.thoroughbreddiesel.com/ 1-886-737-4966. They have the best price I found at $900.00 for 8 injectors. If you can't be good be safe.
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billritter
Active Member

28 Posts

Posted - 09/05/2010 :  09:39:15 AM  Show Profile  Visit billritter's Homepage  Reply with Quote
Stewy, I really do appreciate the you helping me out with this! It does not search for for idle when it starts up. According to records, it had four new injectors about 30,000 miles ago, there are 129,000 miles on the bus. I did unplug the iprs and there was no change in cold perfomance. I am leaning towards pulling the injectors next week.
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94AmTranVolunteer
Advanced Member

264 Posts

Posted - 09/05/2010 :  7:17:23 PM  Show Profile  Reply with Quote
What Body of Brand is the Chassis Mounted on? A AmTran, Blue-Bird, Carpenter, Crown By Carpenter, Thomas, Wayne?

Answering Electrical Problems One at a Time.
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GPwing
Active Member

Canada
32 Posts

Posted - 09/05/2010 :  10:01:52 PM  Show Profile  Visit GPwing's Homepage  Reply with Quote
quote:
Originally posted by billritter

I am leaning towards pulling the injectors next week.



I didn't want to say this earlier because it all to easy to blame injectors as there are so many differnt controls on these engines, but I think you are looking in the right direction.
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Schoolbus56
Senior Member

United States
128 Posts

Posted - 09/06/2010 :  10:26:19 AM  Show Profile  Reply with Quote
quote:
94AmTranVolunteer Posted - 09/05/2010 : 7:17:23 PM
--------------------------------------------------------------------------------
What Body of Brand is the Chassis Mounted on? A AmTran, Blue-Bird, Carpenter, Crown By Carpenter, Thomas, Wayne?





94AmTranVoulnteer,

That DOES NOT MAKE ANY DIFFERENCE TO HIS PROBLEM... Please if you do not have anything to say that pertains to the problem at hand... SAY NOTHING AT ALL!!!!!!!!


Billritter,

Id start checking injectors or some sensors on the engine... Check for loose Plugs loose connectors, Corroded wires.. Anything can be a possibility on the 444E's They can be headaches at times...

Dont worry about the body that is mounted on the chassis Thats just some kids trying to bad mouth some Body builders.

wow.
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billritter
Active Member

28 Posts

Posted - 09/06/2010 :  8:13:27 PM  Show Profile  Visit billritter's Homepage  Reply with Quote
Thank you to everyone who has tried to help me with this. I will be pulling the injectors tomorrow. My dad was the school bus mechanic at the school where I now teach. I spent my younger days in the shop helping dad, but I am rusty now and my dad has passed on. My superintendent asked me to help with the busses due to some difficulty with the mechanic we have been using. It is disappointing to see the condition of the busses are in now, dad would be sick if he knew. Anyway; thanks for all the help! I will post back concerning the injectors asap.
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billritter
Active Member

28 Posts

Posted - 09/07/2010 :  11:54:45 AM  Show Profile  Visit billritter's Homepage  Reply with Quote
so today I cranked the bus and happened to notice that the tach does not move while cranking. Do I need to re-consider the cam sensor?
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GPwing
Active Member

Canada
32 Posts

Posted - 09/07/2010 :  5:51:43 PM  Show Profile  Visit GPwing's Homepage  Reply with Quote
quote:
Originally posted by billritter

so today I cranked the bus and happened to notice that the tach does not move while cranking. Do I need to re-consider the cam sensor?



Memory must be getting short,I can't remenber on a normal startup if you see the tach move before the engine start's, but on a extended crank you do.

How long of crank time are you talking??
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stewyk
Active Member

20 Posts

Posted - 09/07/2010 :  6:21:47 PM  Show Profile  Visit stewyk's Homepage  Reply with Quote
On a long crank you will see the tach move but only after it does a full sweep of the gauges and reset to zero about 15-20 sec. If memory serves me right the cam does not show tach the crank sensor does. The cam is for timing and crank is for speed. One test if you want to try but be very careful is to inject propane in the breather which takes the place of diesel where their is non. Use a propane torch set on with no flame and see if this makes a power gain. Hope this helps.
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GPwing
Active Member

Canada
32 Posts

Posted - 09/07/2010 :  6:49:08 PM  Show Profile  Visit GPwing's Homepage  Reply with Quote
quote:
Originally posted by stewyk

The cam is for timing and crank is for speed.



There is no crank sensor on 444e, only cam.
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billritter
Active Member

28 Posts

Posted - 09/07/2010 :  7:22:00 PM  Show Profile  Visit billritter's Homepage  Reply with Quote
quote:
Originally posted by GPwing

quote:
Originally posted by billritter

so today I cranked the bus and happened to notice that the tach does not move while cranking. Do I need to re-consider the cam sensor?



Memory must be getting short,I can't remenber on a normal startup if you see the tach move before the engine start's, but on a extended crank you do.

How long of crank time are you talking??



GPwing, thanks again for your continued help! I'm not talking about a long crank at all, about as long as it takes to start. Still planning on pulling injectors, just did not get to it today.

Stewyk, Did not crank long enough for the tach to spin I guess. I do not believe this motor has a crank sensor does it? Once again, thanks for your continued help as well!
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billritter
Active Member

28 Posts

Posted - 09/07/2010 :  7:29:11 PM  Show Profile  Visit billritter's Homepage  Reply with Quote
quote:
Originally posted by Schoolbus56

quote:
94AmTranVolunteer Posted - 09/05/2010 : 7:17:23 PM
--------------------------------------------------------------------------------
What Body of Brand is the Chassis Mounted on? A AmTran, Blue-Bird, Carpenter, Crown By Carpenter, Thomas, Wayne?





94AmTranVoulnteer,

That DOES NOT MAKE ANY DIFFERENCE TO HIS PROBLEM... Please if you do not have anything to say that pertains to the problem at hand... SAY NOTHING AT ALL!!!!!!!!


Billritter,

Id start checking injectors or some sensors on the engine... Check for loose Plugs loose connectors, Corroded wires.. Anything can be a possibility on the 444E's They can be headaches at times...

Dont worry about the body that is mounted on the chassis Thats just some kids trying to bad mouth some Body builders.



Thanks Schoolbus56, I will double check connections and the harnesses as soon as possible.
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Schoolbus56
Senior Member

United States
128 Posts

Posted - 09/07/2010 :  8:16:06 PM  Show Profile  Reply with Quote
espically the connections under the engine by the blow by tube

wow.
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billritter
Active Member

28 Posts

Posted - 09/09/2010 :  12:44:58 PM  Show Profile  Visit billritter's Homepage  Reply with Quote
there is very little carbon on the injectors. They actually "look" very good. All 8 were replaced about 30,000 miles ago and I can hear them firing while the engine is running. Still checking the wiring for problems. I can only work on it a couple of hours a week, so progress is slow.

I changed the oil a couple of weeks ago, and it already has some metal in it. I'm worried that the hpop may be letting go. I do not have a computer to check the hpop psi, I may have to get a hold of a 0-3000 gauge and t it in.

Would a bad hpop cause these symptoms?

I dunno guys, might be time to raise the while flag and call a pro. Gotta know when to say when right? Thank you all for your continued patience and help!
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grandyc
Senior Member

United States
58 Posts

Posted - 09/09/2010 :  2:24:14 PM  Show Profile  Visit grandyc's Homepage  Reply with Quote
I know this is going to sound very basic but alot of the inactive codes you have, have alot to do with battery voltage back to the ECM. Did you check the battery connections? Also, If the cam sensor was replaced by a suspect mechanic you probably should make sure he shimmed it correctly. I think its 0.025 to 0.030 air gap is the spec and you will need a tool from Navistar to measure that (part# ZTSE4414.)Usaully when you have a bad Cam sensor it will either not start or shut off once it gets hot which doesnt sound like your problem but worth checking. Alot of the engine stumble problems I have seen usaully have to do with air in the high pressure oil system or on the fuel pressure side of the system. Leaking injector o-rings or stuck IPR valve are usaully the cuprit on the oil side. On the fuel side you need to check the fuel pressure regulator,30-65psi at high idle messured at the fuel pressure regulator is the spec. Also, Its always possible with something this old there is a problem with the ECM or the communication between the ECM and VPM and some of those inactive codes point to that possibilty code 615 for example.
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grandyc
Senior Member

United States
58 Posts

Posted - 09/09/2010 :  6:03:00 PM  Show Profile  Visit grandyc's Homepage  Reply with Quote
One more thing check the connections at the Starter because I believe everything ECM ect junctions threw threw the starter cables. If they are loose it will give you intermittent problems.
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billritter
Active Member

28 Posts

Posted - 09/18/2010 :  9:34:49 PM  Show Profile  Visit billritter's Homepage  Reply with Quote
Ok, after a month of Saturdays things are looking up on this bus. I did t in a 0 to 3000 pressure gauge on the hpop and found it was only putting out 500 psi or so. The bus would not even start at this point. The ipr had just been changed, so I bit the bullet and replaced the hpop. The bus runs great now, but is hard to start. I plan on checking the glow plug relay in the morning. Is there a check valve that keeps oil in the hpop reservoir? It was dry yesterday morning after not being cranked for a couple of days.

Edited by - billritter on 09/19/2010 7:30:50 PM
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efkimes
Active Member

31 Posts

Posted - 09/27/2010 :  06:00:32 AM  Show Profile  Send efkimes a Yahoo! Message  Reply with Quote
The check valve is in the pump. Also with some of those codes or for anyone working on a t444e, if it is a fire wall mounted ECM it is a 3 box system. Inside under the dash is a VPM, vehicle personality modual. If you get it down to thinking it is the ECM and try another one off another bus but that doesn't help then there is a strong chance that it is the VPM. The reason that I post it here is that I recently was working on a 96 444e with cam codes. All wiring was good, ecm was good and it came down to the vpm.
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1stLtDan
Active Member

USA
13 Posts

Posted - 04/19/2018 :  09:15:40 AM  Show Profile  Reply with Quote
If you have acessential to Snapon Pro-link Ultra with Navistar International subscription software, after engine reaches 15o degrees , run the engine testing modes, KOEO then KOEO so you can get a reading on engine contribution testing. Then at least you ll have an idle of which cylinder the injector (s) are the problem ones. Other than that, you ll have to pull the trigger and get them all. Having access to used engines with injectors still in them may save you money but you still have labor and down time to consider. Time is money to most people so make sure you have prices available so everyone know the different cost of going different directions.
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