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[RESOLVED] My car is running like it has 272 cams...but the cams are stock

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Jeff99GS

15+ Year Contributor
1,870
17
Jun 27, 2006
Cleveland, Ohio
So I just bought a 1997 Talon TSi AWD and sold my 420a turbo.

when i bought the talon it idled like shit and was stalling at stop signs....It sounds like it has a set of BIG cams in it...So first i Searched this site and tried a few things before starting this thread.

Here is what i've done so far to remedy the idle/misfire

Boost Leak Test (no leaks)
New Plugs and wires
New ISC
BOV is Recirculated
Tuned SAFC 2 as best i could (fallowed chart on road race enginering)

What else could be wrong with this thing??? could the timing be off??

It also starts to break up/misfire over 4000 rpm at WOT
the exhaust seems to pop...could it be too lean?

anyone with some ideas please help
 
Take a voltometer to your coil pack and make sure that it's good. To me it sounds like one of the cylinders isn't firing and therefore running rough. At higher RPMs, it's dumping enough fuel to ignite in your exhaust system. It also would not hurt to take a look at your timing marks.
 
Take a voltometer to your coil pack and make sure that it's good. To me it sounds like one of the cylinders isn't firing and therefore running rough. At higher RPMs, it's dumping enough fuel to ignite in your exhaust system. It also would not hurt to take a look at your timing marks.

thanks for the advice...what voltage should i see at the coil? am i just looking for 12v at the plug?
 
Dude I Have The Same Problem. My Cams Are All Stock. And I Have People All The Time Comming Up To Me Asking Me If I Am Camming. Or Whatever. And Mine Idles Like Crap Always Stalling Unless I Keep My Foot On The Gas. So I Would Like To Know Some Stuff On This Too Mine Is A 97 Eclipse Gst Spyder
 
How long had you had those plugs put in? I would take them out and look at them. If any of them look wrong, there's the problem. I would most likely expect 1 of them to be rich with fuel.
 
thanks for the advice...what voltage should i see at the coil? am i just looking for 12v at the plug?

OMG You got me! I have no manual handy to look this up. Can someone else chime in about this?

Also, like CrimsonDragon said: Take out your plugs and look for any funny business. Make sure they are gapped correctly. 0.028 with a switchblade style gapper, NOT a disc gapper. Disc gappers are inaccurate, esp. when you're looking for measurements as small as 0.028.
 
Okay, My timing marks are lined up fine...I didnt check the coil yet...but I have NO CEL's on...wouldn't the coil throw a code if it was bad? Tomorrow im going to do an engine compression test...and I'll check the plugs then and let you guys know what i find.

Could this guy have connected the SAFC2 wrong??

The air fuel gauge is ALWAYS in the red :(
even if I richen the fuel with the safc?? I think this guy may have the a/f gauge hooked up wrong...im just gunna get a wideband or something cause this one in th car SUX
 
So I just got done doing a cylinder compression test...and here is the results...NOT GOOD

Cyl 1 has 135 psi
Cyl 2 has 173 psi
Cyl 3 has 155 psi
Cyl 4 has 110 psi


does this mean i need to rebuild the engine?

I did the comp test twice and got the exact same results
 
So I just got done doing a cylinder compression test...and here is the results...NOT GOOD

Cyl 1 has 135 psi
Cyl 2 has 173 psi
Cyl 3 has 155 psi
Cyl 4 has 110 psi


does this mean i need to rebuild the engine?

I did the comp test twice and got the exact same results

Put a couple of teaspoons of oil in that #4 and see if compression jumps back up on it. If so it's going to be the rings, if not you most likely have a leaking head gasket (easier to fix) Or it could be a valve or valve seat, but i wouldn't jump on that last thought until eliminating everything else first.

I'm going t put my money on a head gasket ( or at least hope that's all it is for your sake :D )
 
yeah the 1st clylinder went up to 170 with oil in it...and the 4th one went up to 140?

would this poor compresssion make the car BUCK and surge while WOT ?

If I slowly accelerate about half throttle it seems fine and pretty quick...but the second i go WOT it stutters and chokes??
 
yeah the 1st clylinder went up to 170 with oil in it...and the 4th one went up to 140?

would this poor compresssion make the car BUCK and surge while WOT ?

If I slowly accelerate about half throttle it seems fine and pretty quick...but the second i go WOT it stutters and chokes??

NO, it wouldn't cause bucking or surging under WOT really, my 7 bolt before it went out, it only had 110 in # 3 and 120 in # 4 (HG was leaking slightly already) and i ran mid to high 12's on it all night that night until i turned up the boos and finished off the HG.

Your bucking and choking is going to be something else entirely, what plugs are you running ? what are they gapped at? and last of all...Do you have a wideband, if so what does it read when this happens???
 
No Wideband :( I just bought the car....and NOW i just walked home cause the car will not even run now....It idles at 100 rpm...but then if i UNPLUG the MAF it idles GREAT...but if i try to drive it just sputters????

Im about to cut this SAFC out of here...I dont think this guy i bought it from hooked it up right

I keep getting a 505 code for the ISC but I just put in a new ISC....so why is it still showing that code??

I have BOSCH platinum plugs...the number on the box is 4018

COULD MY ECU BE BAD?

I need some major help...its blowing black smoke now and wont even go above 1500 rpm without getting all choppy and popping black smoke.
I tried to lean it out but that doesn't help does this sound like my MAF or ECU might be bad?
 
No Wideband :( I just bought the car....and NOW i just walked home cause the car will not even run now....It idles at 100 rpm...but then if i UNPLUG the MAF it idles GREAT...but if i try to drive it just sputters????

Sounds like the maf or the safc install to me. Yea, I'd remove the safc and verify no wires are crossed. But if you remove the safc, you'll have to install stock 450cc injectors.

You can check the SAFC wiring. VFAQ Electrical.
 
I suggest you change the plugs to NGK and gap them at .028. How did you do your boost leak test by the way? Base it off of this:
1. Disable your mbc.

2. Turn your motor to 30* ATDC to avoid valve overlap.

3. Start your test at the TB elbow and focus on area behind the TB first.

4. Spray soapy water at TB gasket, BISS, TB shaft on both sides, IM gasket, injector insulators, brake booster, afpr and all vacuum lines/connections.

5. Open your oil cap and listen for leaks. (PCV, valve seals/guide, rings)

5. Listen to your tailpipe for leaks. (EGR, valve overlap, jumped timing, bent/unseated valves)

6. Once all leaks are fixed, move the tester back to the turbo inlet.

7. Spray down the compressor cover (known leak), BOV return/flange (DO NOT TAP YOUR BOV LINE FOR YOUR MBC!!!), IC end tank/fins and all connections. Re- test.

8. Note that you will leak air into the crankcase through the turbo seal but do not panic, this is normal during a static pressure test as long as there are no shaft play.

The desired test result from the begining of the LICP (bypassing turbo) is around 20psi (on boost gauge) with the compressor set at 30psi, while taking no less than 30 seconds to bleed down to 0.

As a reference, my last test on my 500 mile new engine, I was able to pressurize the system to 25psi, bled down to about 16psi (my 1G bov) in about 30seconds, then took about 3 mins to 6psi and just kinda lingered there for a while. It's not easy to do but the point is it's possible. My next goal is 30psi After motor break in and Dodge modding my BOV. A boost leak test is one of most pita but important regular maintenace task, the key is patience and endurance, have fun.

Last, did you ever check the coil pack? Also your A/F gauge is definitely hooked up wrong if it's not even reading how rich you're running. It also is possible that the ECU could be taking a shit. If all else fails, swap in another ECU. Unplug the battery before you do it and hook it back up.
 
OKay thanks for the help guys...I figured out the MAIN problem...One of the wires for the MAF was broken due to the IC pipe clamp rubbing it :(

So I repaired that wire and NOW the car runs again!!
BUT i still have the lil misfire....at idle. Its wierd cause the car pulls strong if i keep it below half Throttle...But if I go WOT it sputters/backfires as SOON as I hit 3000-3500 rpm

MY air fuel gauge is tied to a white wire on the ECU....it also had the BLUE wire from the SAFC connected to it...SO i disconnected this blue wire and it seemed to help my A/F gauge a litte bit...BUT IT STILL NEVER goes green EVER....and I'm sure the car is rich cause of the BLACK smoke coming out of the tailpipe.

Anyway...I will go get the NGK's...and RE-do that boost leak test Like you said and see what comes up! there has to be a LEAK somewhere

:talon:
 
You wouldn't happen to have a 6 bolt swap or a 1g head/CAS would you?

No its Still the 7 bolt
according to this guy I bought it from it is all original expect for the mods in my profile

Im Re-doing the WHOLE intercooler piping right now cause it had like 25 couplers on it haha...so I have to get this all set before i can continue my investigation into the misfire....the guy I bought the car from was kind of a hack :( all the stuff he added on was installed poorly....but other than the stuff he touched the car is in great shape!!

The only code the car gets is that PO505 my book say IAC circut...but I just bought a NEW IAC (ISC) so it must be a vaccum/boost leak up by the manifold somewhere....

If i did have a boost leak in my manifold would it make it misfire at idle?
Im not even sure its a MISFIRE....My car sounds like an old Muscle car with cams....or a eclipse with big cams...its lope-ing....can i check my timing with a timing light somehow?
 
Change Fuel Filter. And Double check that Fuel Pressure, 43.5 Psi. at Idle with the Hose off and pluged. Beshure put the hose back on after adjustment
 
No its Still the 7 bolt
according to this guy I bought it from it is all original expect for the mods in my profile

Im Re-doing the WHOLE intercooler piping right now cause it had like 25 couplers on it haha...so I have to get this all set before i can continue my investigation into the misfire....the guy I bought the car from was kind of a hack :( all the stuff he added on was installed poorly....but other than the stuff he touched the car is in great shape!!

The only code the car gets is that PO505 my book say IAC circut...but I just bought a NEW IAC (ISC) so it must be a vaccum/boost leak up by the manifold somewhere....

If i did have a boost leak in my manifold would it make it misfire at idle?
Im not even sure its a MISFIRE....My car sounds like an old Muscle car with cams....or a eclipse with big cams...its lope-ing....can i check my timing with a timing light somehow?

Never expect a new thing to always be working. I would take the IAC out and double check it to make sure it is working properly via through the manual way. If it checks out ok, reinstall it. A boost leak would make you run like the rich pig it is running and would cause it to break up at WOT due to the rich mixture. It sounds like something is sealing correctly at low boost but at high boost it seperates from the air pressure and causing the leak. My guess is definitely around the TB area especially the seals but a mistightened intercooler pipe would do the same as well.

I bet you aren't misfiring but just running really crappy. The lack of a CEL supports my theory but barely.

Also, I would check all vacuum lines for tiny pinholes. This is where soapy water works best. If you have stock piping, spray it all over the lower and upper intercooler pipe. Just follow the BLT I posted above.
 
Well I changed out the bosch plugs for the NGK and Gapped them right, and NOW it DOESN'T break up or get choppy in the HIGH RPM range anymore!!!! It still idles like it has BIG cams tho LOL. I think my other plugs got SOO fouled out from it running rich that it was blowing the spark out when i went WOT?!?!

Now all I have to do is figure out this idle and she will be ALL fixed! I am going to do another boost leak test today!

Thanks for all the help guys!
 
Or maybe the plugs just....suck...
So it still runs rich right? That boost leak test should tell you if you have any leaks or not. How's that SAFC coming. Did you remove/rewire it yet? If it's still running lean, you might want to move it to the temperature sensor. Check to see if that's working properly.
 
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