So I Installed BC 272's..

[Shane2GSX]

Just as the title says, along with a mitsu mutli layer hg and ARP's. Started it up last night, and everything seemed fine. The thing sounds flat out nasty (in a good way). But, when me and my bud take it for a drive, the idle starts going crazy everytime we stop. When cruising or giving it a good amount of throttle, all seems fine. When we stop, it seems to want to die, and it did a few times. It also bucked on a few occaisions when the RPM's were approaching 1000. We pulled over and adjusted the throttle cable to remedy the problem temporarily, but we had trouble getting the RPM's to stay around 1k. They constantly fluctuate.

When we did the Cams, we did not note the orientation of the CAS (97-99), so I'm thinking that could be it, and I will try reversing it. Also, we got a CEL just before putting the car up for the night, so I'll get that checked as well.

Besides those things, does anyone else know anything else that would cause this?

BTW, timing is good, it's been double and triple checked. Thanks.

 

[Shane2GSX]

5-10 is way too low for 272's, you probably have a vacuum leak somewhere. Vacuum should be around 15 at idle with those cams. That would also explain the idle problems you're having. I would do a boost leak test just to make sure. I also wouldn't try to raise the idle higher than the factory idle setting, that can cause idle surge.

What are you using for tuning right now?

Nothing, DSMLink is on the way to me as we speak. Currently turbo and fuel are stock. Fuel is also on the way, turbo setup in about another 3-4 weeks..

 

[Shane2GSX]

Agreed, I was going to say, 5-10 is pretty low for 272's. Possibly for 280's it's a little more feasible. Anyway, He listed that DSMLink is on the way. In that case, once it's up and running just click GROUND ISC and adjust your BISS the proper way. Then set your idle RPM to around 850 or 950 and you should be good to go.

Damn I love DSMLink

What do you mean by, adjust your BISS the proper way?? I thought you just screwed it in to lower idle, unscrewed it to make it rise??

BTW, ordered the BISS and they said it comes with an O-Ring and Cap.. I don't remember seeing an O-Ring with the other one..

 

[blcknspo0ln]

wow.. if you didn't have an Oring with your other BISS that would account for a major boost leak. Good thing you're getting that squared away.

What I mean by "properly" adjusting the BISS is by grounding/temp.disconnecting the ISC. The ISC is a motor that pulls a plunger in and out and therefore is the ECU's attempt to maintain a particular idle speed. By adjusting the BISS while the ISC is still going, to put it simply, you get an uneven mix of adjustments because the ECU is trying to selfadjust idle by the ISC and you are manually changing idle by the BISS. What happens when you ground your ISC is you basically then manual set your BISS to your desired engine idle speed and then you unground the ISC. This way your ISC has "learned" your particular desired idle speed.

It's not hard, really.

 

[Shane2GSX]

Okay, thanks for the information. That would explain why, when I had the car running and I was adjusting the BISS, it didn't seem to make a difference. But then, when I turned off the car, adjusted the BISS, and turned the car back on, it then changed.

So is it true then that I could just turn the car off, adjust, turn car on and test, repeat if necessary? Wouldn't this accomplish the same thing?

 

[scottsee]

This should be helpfull with your Idle tuning when you get Dsmlink. http://scottjsee.googlepages.com/dsmlinkidleadjustments

Also, I'm really looking forward to installing my BC272/ARP combo. Get a sound clip up for us...

 

[Shane2GSX]

Wow! Very nice in depth write up! I'll definitely use that to help things out..

I'll get a Vid up of my car idling probably sometime next week. Sounds pretty nasty..

 

[daren_p]

Have you gone in to very that all your marks are 100% on? Don't just eyeball the cam gears, use a straight edge against the head surface. I'm not sure about th BC's but alot of the other 272's don't idle very lumpy. Even 10" sounds abit on the low side to me for that size of cams, with a factory idle rpms I would think a couple inches more vac. If your timing marks are off at all this could explain why your vac seems low & the idle is lumpy.

 

[blcknspo0ln]

read a couple of posts in, he said the BISS was missing the Oring. If that was wrong, who knows how many other boost leaks he has.

 

[Shane2GSX]

Have you gone in to very that all your marks are 100% on? Don't just eyeball the cam gears, use a straight edge against the head surface. I'm not sure about th BC's but alot of the other 272's don't idle very lumpy. Even 10" sounds abit on the low side to me for that size of cams, with a factory idle rpms I would think a couple inches more vac. If your timing marks are off at all this could explain why your vac seems low & the idle is lumpy.

When we did the timing, we used the straight edge of an allen wrench to ensure that the timing marks on the cam gears were lined up with the surface of the head. Down on the crank, we ensured that the notch was lined up with the little tab that's at about 10 o'clock..

If this is wrong and you know a better way, please tell me.

When we did the cams, we also did ARP's and a HG, so we had to take the head off. We left the IM and EM attatched, unplugged everything we needed to, and pulled it. Three of us checked the motor 3 times before firing it up, so I don't think we're missing any hoses, but there still could be a boost leak somewhere.

Is there a way to tell though DSMLink if timing is off?

 

[Shane2GSX]

read a couple of posts in, he said the BISS was missing the Oring. If that was wrong, who knows how many other boost leaks he has.

I never said it was missing the Oring, I said after the screw blew out, I didn't see it. But that leads me to the question, is the Oring visible with the screw in??? If so, I did not see it before the BISS blew out. There was not a cap on the BISS either..

 

[Dream On]

You can't see the oring with the screw in. If you're going to adjust the idle, do it the right way also.

http://www.plymouthlaser.com/biss.htm

 

[Shane2GSX]

Aweseme link, thank you! But does all that apply for a 2g???

 

[Shane2GSX]

Have you gone in to very that all your marks are 100% on? Don't just eyeball the cam gears, use a straight edge against the head surface. I'm not sure about th BC's but alot of the other 272's don't idle very lumpy. Even 10" sounds abit on the low side to me for that size of cams, with a factory idle rpms I would think a couple inches more vac. If your timing marks are off at all this could explain why your vac seems low & the idle is lumpy.

Just a quick question. If the timing was off, wouldn't it run like crap over all, instead of just at idle? At WOT, the car seems great.

Also, if the CAS was 180* off, wouldn't it run like crap over all?

 

[daren_p]

Just a quick question. If the timing was off, wouldn't it run like crap over all, instead of just at idle? At WOT, the car seems great.

Also, if the CAS was 180* off, wouldn't it run like crap over all?

It may not run 100% all over but it may not be noticeable. I would just verify the marks again just to be sure. The marks may have been dead on when you tensioned everything up but it is possible for it to jump if the auto tensioner didn't do its job properly upon startup. This very thing happened to me when I installed my cams & it wasn't very noticeable as far as performance, just the extra lumpy idle & low vacuum.

 

[Shane2GSX]

Okay, thanks. I'll check it out and report back..

 

[Raph]

Did you all know that Hyundai Dealers have a Camgear lock tool(from Kent Moore/SPX) for older 4g63s.. (like ours) .. i have one and use it everytime i do a timing belt job (you still have to take it out to lay on the elt, but it helps to check the timing afterwards, and holds the Cam gears steady when you take the Belt off. )

 

[Shane2GSX]

Okay checked the timing, and it's perfect. TBelt nice and tight, all marks line up. Marks on pulley's line up with straight edge to the top of the head..

Some things to note are:
There's a sensor, not sure what it is, on the very top of the IM with two little wings that hold screws and a circular piece about the size of a nickel that fits into the IM. One of the wings actually broke when screwing it back on, so I guess that could cause a problem??

Also, when I try to start it with it being dead cold, it will not start with out me getting on the throttle to help it a little. It smells like unburned fuel as well. So maybe it's just a matter of tuning?

I guess my things to check are:
Once DSMLink get's here, CEL.
Vacuum Leak
CAS

If anyone can thing of anything else, please let me know.. thanks.

 

[daren_p]

Where abouts on the intake mani is this sensor? Sounds like you could be talking about the MDP? Looks like the black unit in this pic:

http://www.roadraceengineering.com/parts/mdp_adapter/mdp_adapter001.jpg

If it is infact this sensor, that could defently be a source for a leak.

 

[Shane2GSX]

Yep, that's it.. here's another pic to verify

http://members.shaw.ca/dsm.1000q/Engineprimer/2G/mdp.htm

Looks like I'll be ordering that.. I bet that's what my CEL is..

I wait till link gets here to make sure, since it's a $106 part..

 

[Shane2GSX]

Little update:

I finally got link and installed it tonight while keeping the injectors, fp and all else stock so I could troubleshoot the problem. I adjusted the idle to 1000, zero'd out my global and deadtime, inverted my cas, swapped plugs 1 & 2 and 3 & 4, and setup the values to be captured with what you guys suggested. I then installed my used MDP sensor and logged 3 tries to start the car. No luck at all. The car would not start, even with a little throttle.. Also, since I changed the ECU, I have no way of knowing now what that CEL was.. Nice..

At this point, I'm lost and have no idea what the problem could be.

My car has been down for 3 weeks now and counting, and I'd really like to get this thing running...

Here is the link to my thread on DSMLink forums.. I posted 3 logs of trying to start the car on there..
http://www.dsmlink.com/forums/showthread.php?t=13601