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aaronwilmoth80911
Senior Member

123 Posts

Posted - 08/26/2013 :  3:59:57 PM  Show Profile  Visit aaronwilmoth80911's Homepage  Reply with Quote
I have a 2002 Amtran with a T444e that will not boost correctly. The EBP sensor and MAP sensor have both been changed. Ran fine until it came in for the timing cover leaking coolant. Checked CAC and all hoses and clamps. Thinking maybe the EBP valve, not sure how to check it though. Any ideas would be much appreciated. Thanks!!

Fastback
Top Member

985 Posts

Posted - 08/27/2013 :  05:14:01 AM  Show Profile  Reply with Quote
If the CAC was removed during the front cover repair procedure were paper towels or rags used to plug the openings? Removed before reassembly?

Why yes, the ORIGinal CHARGER is a Fastback
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aaronwilmoth80911
Senior Member

123 Posts

Posted - 08/28/2013 :  09:03:00 AM  Show Profile  Visit aaronwilmoth80911's Homepage  Reply with Quote
I had some extra pipes and hoses laying around so i took the CAC out of the equation completely and routed pipes without the CAC at all and it made no difference. I have 65 PSI fuel pressure at the filter head which is spec. Supplied air to my wastegate actuator and it seems to be working ok (no real spec on how much it should move). Talked with an International Tech and told him everything I had done and he was pretty well stumped. Turbo shaft does not have movement, not passing oil. I have replaced MAP sensor with a known good one from a different bus as I sometimes get an inactive code for MAP signal low. ICP desired pressure and ICP actual pressure are very close, so I don't believe its a HPOP or IPR issue. When I first started messing with this a couple weeks ago I had 17PSI oil at idle and 33PSI oil at high idle or loaded high idle. Now I have 45 PSI oil at idle and about 55 PSI oil at high idle or loaded. Extremely frustrated right now!!! Thanks!!!
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Fastback
Top Member

985 Posts

Posted - 08/28/2013 :  10:58:15 AM  Show Profile  Reply with Quote
Are you positive it was running fine before repair? Might check for excessive back pressure...air inlet restriction...etc.

Why yes, the ORIGinal CHARGER is a Fastback
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aaronwilmoth80911
Senior Member

123 Posts

Posted - 08/28/2013 :  11:01:57 AM  Show Profile  Visit aaronwilmoth80911's Homepage  Reply with Quote
I talked to the driver of the bus and he said it was running fine before it came in to the shop over the summer for the coolant leak to be fixed. Also went through records to see if any problems like this had been reported and there were none. I dropped the downpipe off to ensure that the EBP valve is opening all the way and it is. The last time I ran it down the road with the computer hooked to it, My back pressure was around 20-21 and boost was around 8-9.
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aaronwilmoth80911
Senior Member

123 Posts

Posted - 08/28/2013 :  11:17:42 AM  Show Profile  Visit aaronwilmoth80911's Homepage  Reply with Quote
Also just an FYI, I am not the one that did the original repair. I am now the 3rd person to work on this bus to try and figure out what is wrong. I did the same timing cover repair on another bus at the same time as this one and it went out running fine and has not been back for any issues since.
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Fastback
Top Member

985 Posts

Posted - 08/28/2013 :  12:28:44 PM  Show Profile  Reply with Quote
The way you were wording it I had a notion you did not do the original repair, 3rd person to work on it? Sounds to me like you should go from square one and go step by step through International's Performance Diagnostic sheet at this point.

Why yes, the ORIGinal CHARGER is a Fastback
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aaronwilmoth80911
Senior Member

123 Posts

Posted - 08/28/2013 :  8:17:37 PM  Show Profile  Visit aaronwilmoth80911's Homepage  Reply with Quote
Been there and done that for the most part. I don't have a breakout box so some of the tests were not able to be done as easy, but for the ones that I needed the breakout box for, I was able to get readings with ServiceMaxx or check the mechanical portion of things (EBP Valve) Went step by step through the diagnostics in the manual and everything is passing. Did KOEO tests and everything passes, did KOER tests and everything passes. It seems to idle well, but when you put your foot in it, it sputters and hesitates and stumbles all over itself. I am totally stumped at this point and wanting to throw in the towel. Very frustrating having to clean up someone elses mess.
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Fastback
Top Member

985 Posts

Posted - 08/29/2013 :  05:03:00 AM  Show Profile  Reply with Quote
Well you were suspicious of restricted exhaust when you dropped down pipe and checked EBP valve, have you tried driving it with muffler disconnected?

Why yes, the ORIGinal CHARGER is a Fastback
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aaronwilmoth80911
Senior Member

123 Posts

Posted - 08/29/2013 :  08:38:35 AM  Show Profile  Visit aaronwilmoth80911's Homepage  Reply with Quote
Yea I tried that and had no luck there either.
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aaronwilmoth80911
Senior Member

123 Posts

Posted - 05/02/2014 :  07:14:23 AM  Show Profile  Visit aaronwilmoth80911's Homepage  Reply with Quote
I was thinking about this issue today and forgot that I did not post a response to the post when we found the problem.

The issue was in the quick connect fittings on the HPOP. The fittings were unscrewed from the HPOP instead of having the quick connects released. When this happened, one of the springs fell out of one of the fittings, allowing the little disc inside the fitting to float around freely. When the engine was running, it would sometimes get sufficient oil flow through the oil passage in the head, sometimes not, and would not let the injectors work as they should. We wasted a lot of time and money on this issue, for something relatively simple and silly.

Thanks for all the input from everyone!!
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Fastback
Top Member

985 Posts

Posted - 05/02/2014 :  08:06:58 AM  Show Profile  Reply with Quote
Thanks for the update, what an ordeal. I guess I should feel fortunate being the one man in a one man shop, at least if something's not right after a repair I can retrace my steps.

Why yes, the ORIGinal CHARGER is a Fastback
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