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Cas install causing poor performance

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mintalontsi

Proven Member
42
1
Sep 11, 2014
Clifton, New_Jersey
Hi all, for the past couple of months i've had a cel for my cas. Recently it started to get bad with the car breaking up and hesitating under wot. I replaced the broken cas with a new cas from rockauto. I set the motor to where the cam angle marks lined up, installed cas, grounded, and set base timing to 5btdc using an adjustable timing light. I then started the car and noticed that it idles higher at 2k rpm and then goes to 1k once it's at operating temperature. The car used to start at 1500 rpm and drop to 850-1000rpm after a minute or 2 with the broken cas. When driving, the boost isn't hitting as hard (it's more linear vs when it hit hard with the older cas) and it's taking longer to come into boost (15-16psi at 5k vs around 35-38 w/older cas). The car is also hesitating high in the rpm's. I thought maybe it's a boost leak from the throttle body so i replaced the gaskets and torqued to spec and still the same problems. What do you guys think is going on?
 
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I figured that the maf would be good.
Your mafs is is fine as pauleyman has said. Your flashed tune on that keydriver chip compensates for the extra air from the removed HC. See your posted pic below. where it says (NO LOWER H). It should say HC (the C has been cut off) HC means Honey Comb.

If all you changed was cas and it boosts so late I think your timing is still off and or you have it installed 180 out. Cause and effect here.

+1 . Your timing is off Either the MECH or the ignition. Not trying to berate you, but do you know any other DSM'er around your area that can put a second set of eyes on it? You have been dealing with this for awhile. The ultra late spool up for that 16g is a big indicator.
 

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I want pics of your timing marks. I'm not convinced. Are you comfortable doing a tbelt job?

Yes, i did the t-belt roughly 3000 miles ago and then i re-did it twice to check mechanical timing back in february i can do it again if need be. Today i aligned the cam marks and the HB mark lined up with the TDC mark on the timing cover. I also checked the timing on the motor with the plug grounded and idle between 750-850 and the HB read 6-7btdc. I then tried what linksys42 was saying about setting the gun to 10, aligning the cam gears and the setting the gun to zero and seeing if there was any correspondence on the HB. So, i adjusted the cas with the gun set to 10btdc (i've read waste ignition makes that 10 setting about 5btdc) until the cam marks lined up. I then zero'd out the gun and aimed it at the HB and the HB read around 3-4btdc. Then with the gun set at 10btdc and aimed at the HB the hb read 1btdc.

Just a thought but, back in February when i checked the mechanical timing, with the motor at tdc on compression stroke, the HB pointed to TDC on the timing cover. This is with the crank, oil pump, and cam marks lined up. The tensioner pulley holes were installed at somewhere around 9 and 12 to 10 and 1 o'clock positions. When i removed the tensioner, i put the grenade pin in the top to check for any leaks and some fluid was on the pin as was evident as i wiped it on a paper towel. Maybe a quarter of a droplet worth of fluid if that. I compressed the pin in a vice at about 1 to 2 complete turns per minute and installed the pin.

There was no oil, fluids, or grime in the timing belt area. This issue started as a cutout every now and then at the top of 3rd and then became a hesitation, cut out (sounded like a stutter box or an antilag system) and back fire under full throttle through turns illuminating the cel and then the cel going off shortly after (would always happen on the same sharp turn highway underpass). This progressed to the same thing on the straight away with the cel staying on. Then i thought it was the cas and after re-installing and messing with different cas's (and realizing it wasn't a cas issue) the problem progressed to very laggy turbo and back firing. Could a faulty tensioner be screwing with my timing?

Your mafs is is fine as pauleyman has said. Your flashed tune on that keydriver chip compensates for the extra air from the removed HC. See your posted pic below. where it says (NO LOWER H). It should say HC (the C has been cut off) HC means Honey Comb.




+1 . Your timing is off Either the MECH or the ignition. Not trying to berate you, but do you know any other DSM'er around your area that can put a second set of eyes on it? You have been dealing with this for awhile. The ultra late spool up for that 16g is a big indicator.

I'm not taking it as berating, i really appreciate the help everyone here is providing. Not really. I have a buddy who used to do GVR-4's in high school but he's pretty unreliable when attempting to meet up. I've only seen 2 other dsm's in my area during my 3 years of ownership smh. When this issue is ironed out i have to find some dsm events around here and make some dsm friends LOL.
 
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Just post up a pic of the cam gears when it's at tdc

After adjusting the ignition timing yesterday and test driving it today the car isn't as bad as it was. It's not back firing anymore and only breaks up/slightly cuts out under boost. The response and spool time is still laggy but not as bad as before. It pulled like hell in the upper rpms for the first time since this timing issue began.
 

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Your mechanical timing look spot on. So that doesn't seem to be the problem.

Yes, It's definitely not the mechanical timing. There is still something going on that's causing my timing to retard. I don't get it. Is there some sort of magic spell involved LOL? I've triple checked everything, tested CAS, tested coil pack, tested power transistor, checked mechanical timing, auto tensioner, ecu, blt. Car is running rich and has nowhere near the power it used to have. All i can think of is ecu, wires to cas (unlikely imo), faulty auto tensioner?
 
Out of curiousity, how old are your spark plus & plug wires? Sorry if you've already covered this but I don't have time to review this entire thread ATM.
 
Out of curiousity, how old are your spark plus & plug wires? Sorry if you've already covered this but I don't have time to review this entire thread ATM.

All good. The plugs and wires are less than 500 miles old. plugs are ngk bpr7, wires are ngk
 
All good. The plugs and wires are less than 500 miles old. plugs are ngk bpr7, wires are ngk

My plugs had less than 10 miles on em. About 10 months with no start.

I tried to start the car, checked everything, all sensors were good, had spark.

Turns out the plugs were fouled, car did not want to start.

Boom, put some new ones in and started right up.

Simple things my friend, always.
 
My plugs had less than 10 miles on em. About 10 months with no start.

I tried to start the car, checked everything, all sensors were good, had spark.

Turns out the plugs were fouled, car did not want to start.

Boom, put some new ones in and started right up.

Simple things my friend, always.

Just checked my plugs and they are black. I cleaned them with a torch and wire brush and the car seemed to accelerate a little better (could just feel fast compared to the altima i've driven for the past couple days) altough it's still not coming on hard into boost. Maybe i should get a set of bpr6's and 7's and see what happens?

Usually at part throttle i can feel it spooling and waking up. Not so much now smh.
 
Just checked my plugs and they are black. I cleaned them with a torch and wire brush and the car seemed to accelerate a little better (could just feel fast compared to the altima i've driven for the past couple days) altough it's still not coming on hard into boost. Maybe i should get a set of bpr6's and 7's and see what happens?

Usually at part throttle i can feel it spooling and waking up. Not so much now smh.

Dude, mine were the same way.

I threw on some cheap plugs from advance auto parts just to see if it was my problem, and it was!

The car started up right away.

I don't have anyone selling NGK's here, so I opted to use cheap ones just to see what would happen.
 
This car is giving me this problem on and off. It spools nicely now (put a bleeder hole in the mbc:thumb:) and pulls hard sometimes. Other times, under wot through a turn, it'll backfire and sound like a stutterbox and won't power through it. It also cuts out for a split second high in the rpms then returns to accelerating. while it does this, the stock boost gauge needle will jump. Could this have something to do with the factory boost control solenoid or is the tune just wacky?
 
Other times, under wot through a turn, it'll backfire and sound like a stutterbox and won't power through it. It also cuts out for a split second high in the rpms then returns to accelerating. while it does this, the stock boost gauge needle will jump. Could this have something to do with the factory boost control solenoid or is the tune just wacky?

It is premature detonation (knock). GET A LOGGER!!!! (Last time im going to say it). Your eprom was flashed for your set up, and it also converted the stock boost Gage to a knock gage. If you see that gage move get out of the throttle or your going to damage your motor. You shouldn't be romping on it till you get your issues figured out. Take it to the nearest reputable tunning shop (preferably that specialize in DSM's or evos) to diagnose it, before you do some major damage. And once you find out the issue please post/update what the cause was. Good luck.

Take a look at the link I provided by DSMchips/keydriver. The information is under how does the knock gauge work.
http://www.dsmchips.com/faqs.php
 
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It is premature detonation (knock). GET A LOGGER!!!! (Last time im going to say it). Your eprom was flashed for your set up, and it also converted the stock boost Gage to a knock gage. If you see that gage move get out of the throttle or your going to damage your motor. You shouldn't be romping on it till you get your issues figured out. Take it to the nearest reputable tunning shop (preferably that specialize in DSM's or evos) to diagnose it, before you do some major damage. And once you find out the issue please post/update what the cause was. Good luck.

Take a look at the link I provided by DSMchips/keydriver. The information is under how does the knock gauge work.
http://www.dsmchips.com/faqs.php


That makes sense now. I ordered an aldl cable for obd1 to usb from reddevilriver.com along with tunerpro rt. I've followed the cd-rom, youtube tutorial ,and dsmtuners write up and the program will not connect to the ecu. Can anyone suggest another datalogging program or is this cable/program garbage?

https://www.ebay.com/itm/Mitsubishi...294059?hash=item1c921a7e2b:g:aawAAOxybi9Re0~d
 
This.
http://mmcdlogger.sourceforge.net

I don't know if you can get it to work with that cable though. Maybe with a palm emulator. You can always make your own cable there's instructions on that site to do so.

I don't think it's the cable or software but the obd1 port itself. My friend has a shop and he tried using his snap-on diagnostic scanner with the proper obd1 adapter and it wouldn't even power on.
 
Try swapping those plug wires with a set from a known good car, although NGK makes great plugs...they make LOUSY Dsm spark plug cables!
 
Stock are the best by far.

That will be the next thing i do then. As an update, i sent my ecu out to dsmlink to test and have serviced. They said the boost control solenoid driver was bad and replaced that. They also replaced the electrolytic capacitors as preventative maintenance. Told me it was a non-turbo ecu that was converted. They said they were able to connect to the ecu through an obd port and did not get a cas code. They said it may be a wiring issue.
 
So, i tested the wires going to the cas with the key in the on position. The cam and crank wires aren't getting the 5v they're supposed to. From my research these wires lead to the mfi relay? Does anyone know where the mfi relay is located?
 
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