2003 ISX suggestions needed

[DDlighttruck]

(07-28-2017 )Billdozer2 Wrote:  Although my engine is different, I have a 2250, I was having issues with turbo cough. Randomly while climbing a hill, the boost would hover right around 30 psi or so, turbo would cough, boost would drop to around 15 psi, and then climb back up to the low 20's. Sometimes the boost would go no higher than 20 psi all day. No check engine lights. Nothing. Using information from this forum, I decided to replace the sensors that directly deal with boost information to the ECU (Thinking that incorrect information was being sent to the ECU) I replaced the IMAP and the Exhaust Gas Pressure Sensor. Turbo cough is gone. Fuel mileage is up. Boost pressure is back up and truck is running great, for now.

I know it may sound silly to replace sensors even though the truck is not telling you that anything is wrong, aka Check Engine Light. Cummins Quickserve even says that you should not replace the IMAP just because it has soot in it. But, the sensors on these engines get covered in soot and start sending false information to the ECU. They should be replaced as preventative maintenance.

I'm going on blind faith that what you and everyone else has said. Arguably $1200 isn't a lot of money but it's hard to swallow when there are no codes or justification to do so. Some of that is a low coolant sensor and a rear axle temp sensor but still. That is a chunk of change.

So tomorrow we pull a lot of stuff apart and put it back together. Hopefully the money is recouped in fuel savings. I appreciate the advice I don't have an issue spending the money if I see the return.
Thanks

[Billdozer2]

(07-28-2017 )DDlighttruck Wrote:  I'm going on blind faith that what you and everyone else has said. Arguably $1200 isn't a lot of money but it's hard to swallow when there are no codes or justification to do so. Some of that is a low coolant sensor and a rear axle temp sensor but still. That is a chunk of change.

So tomorrow we pull a lot of stuff apart and put it back together. Hopefully the money is recouped in fuel savings. I appreciate the advice I don't have an issue spending the money if I see the return.
Thanks

If the other sensors look like the one you posted, I'd be shocked if you don't see an improvement. I'd also go ahead and do the overhead. Doesn't hurt to know that it is done and done correctly. You could do this yourself with Rawze's overhead video. (That is if the 870 and 871 overheads are the same. I'm not familiar with either engine.)

The members of this forum are good people. Many have come here after going down the wrong path, lost and broke with a truck that just doesn't want to make money. We try and help out any way we can because we know how temperamental the ISX can be and Cummins isn't going to help you. This is mostly because they would rather you come back as many times as possible and/or they don't know themselves.

Just keep an open mind here and don't take it personally if Rawze replies using the big red fonts. Haha!

[Magard]

Sensors at home on your schedule are a lot better than problems on the road 1000 miles from home and at the mercy of some idiot mechanic. I would just call it good business practice and move on. Just imagine the bill you might have beat will that 1200. It will help the sting in the pocket book. Your doing well, seeking good advise.

[Waterloo]

Spot on advice. When I first bought my money pit, I was having all sorts of EGR issues on my CM-871. I found Rawze via Google and his EGR Tuneup videos. After thousands of dollars at shops that never fixed the truck, nor ever suggested replacing any sensors, and tens of thousands of dollars in lost revenue, I said F it and replaced all of the sensors. What could it hurt, I was already near bankruptcy and losing my house... Guess what, it worked! I saved the house and then went on to MM the motor which revealed even more serious issues, my bad head. But, Rawze and the many great guys here on this site allowed me to financially recover and eventually in frame the truck. Rawze and company along with all of the very sound advice and help here is priceless. You are on the right path DD. ;-)

[DDlighttruck]

               

Progress. I think it looked pretty clean.

[DDlighttruck]

Last picture the sensor to the right of the new one has nothing connected to it. Is that normal?

[Waterloo]

Not bad! Looks good! Get that Carb Cleaner out and start scrubbing! LOL! You will have a new truck when you are finished. You should feel it the minute you fire her up. One thing too, the air compressor. If it is really knocking, there is a rebuild kit for it, it runs around $500 and you can do it yourself if you are up to it. The compressors on these ISXs rarely fail, it is usually just a bad head/gasket that needs to be replaced.

Also, your Damper, 500,000 miles on those, they do go bad. I replaced mine back when I was having issues and it cured a few problems, really smoothed out the motor. Just something to think about. oh, and the damper needs to be painted, no paint, no warranty. Hope this helps.

[Waterloo]

No clue on that sensor to the right... Almost looks like a temp probe? Someone will chime in.

[DDlighttruck]

Its already cleaned and back together. I chickened out on the metal tube leading to the exhaust pressure sensor, I know how to do it, cut the tube off, heat it up, use a ratchet and a socket to spin it out. BUT if that doesn't work, then on a Saturday I'm stuck. I'll leave it and let a shop do it when there is time. Then if it doesn't work it's their problem. I need to go to work on Monday.

The EGR differential tomorrow, and look for the delta P.

Thanks for the heads up on future repairs Waterloo