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99n/a Code P1390 after tb change, bad sensor ?

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shaggy19702

Probationary Member
2
0
Aug 3, 2003
DelawareUS
Ok, so i figured i'd save a few bucks by doing my own timing belt. I finished it on sunday, and shortly after starting the car began to idle a little rough, not enough to stall, just a little bumpy. After driving the car 1/4 mile the engine light came on. The resulting code was 1390 which i understand to be timiing belt off 1 tooth or more. I double checked the timing i can't tell you how many times before bolting everything together. If the camshaft or crank sensor were not working properly would they have their own problem codes ? Also, assuming my belt is actually off 1 tooth, would the engine even run ? The vehicle runs fine, the engine revs and drives like normal, apart from the rough idling.

The last question i have. Is there any other way to remove the 2 long motor mount bracket bolts ? I ended up jacking the motor up just to remove the front bolt, and then i was able to pull the bracket and bolt out. I must have beat myself in the head for 3 hours trying to get those 2 bolts out, they just have so little clearance between the block and the fender.

I plan on volt testing both sensors this evening.


Any help would be greatly apprciated.


-=<> Aaron <>=-
 
Anyone ??? We took the belt off again, and re-alligned everything and double checked it again and again.. It's still coming up with the same error code, and it still idles bad..

Any ideas ?

-=<> Aaron <>=-
 
Ok I was having the same P1390 code pop up and I checked the Timing several times...I also replaced the cam and crank sensors and still had the problem...Just yesterday I got it figured out! My belt was slipping so I replaced it but before I did that I had disconnected the batt...So when I reconnected it, the computer relearned the system while the timing was off 39 degrees.. All you have to do is take it to a mitsu dealer and tell them to use their little scan tool (Only dealers have it apperently) and hit the relearn button! the car will then give you a set of instuctions...for example...drive 16 miles and put more gas in it. after all that the computer will begin its tests and presto! Fixed! sry so long.:boring:
 
The TB can be off a couple teeth and still run but will idle rough. If your getting P1390 you most likely are off a tooth (ECU can tell). CAS and CPS have their own fault codes if they are bad. It's sometimes very hard to see if it's off a tooth. The belt has to be fully stretched and tensioned correctly and crank pulley rotated in the forward direction and then stopped without letting it go back at all when you check. It helps to place a straight edge across the middle of the cam sprockets bolts to see how the marks line up on both sides of both sprockets. People often put the TB on off a tooth deliberately because it will shift back correctly after it's stretched and tensioned.
 
im having the same issue.I just don't understand how it can actually skip any teeth at all.?? the tensioner puts pressure/tension and holds it in place snug and tight .so if anything my tensioner would be the one causing all this trouble. right? if all the marks line up. Its annoying how this car can either relearn people say to take to Mitsubishi and others say its actually off a tooth but in reality, its not at least in my case . so whats the fix .
 
It's usually installed off a tooth and sometimes it's very hard to tell - you'll swear the marks all line up.

I know yours is a NT but for the 2g turbo TB install, it helps if you turn the exhaust cam sprocket 1 tooth off when putting TB on to account for any slight cam sprocket rotation when TB is fully tensioned. Also for after turning crank 6 times and waiting 20 minutes for TB to settle. Read note on step 33 here: http://www.vfaq.com/mods/timingbelt-2G.html.

You may have the same issue on your NT - read step 13 here (http://2gnt.com/index.php?d=Timing_Belt_Replacement).

It's also deceiving as to aligning the cam sprocket marks. You not only have to align them but they also must be even with the top head surface (which is hard to see when the head is 1 inch away from it). A trick is to place a straight edge across between each cam shaft center and align the marks against it instead of the head which is further away.
 
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