negative symptoms of LW Flywheel and crank pulley?

legacy92ej22t · Post by **legacy92ej22t** » Sun May 22, 2005 3:47 pm

Of running a LW flywheel and a LW crank pulley?

Ever since I did the motor swap the new motor hasn't been 100% but ever since the clutch, flywheel install it's running really bad. The engine is acting like it's starved of fuel when on partial throttle. It bucks and stumbles and will even backfire sometimes (not after fire) when you just try to maintain a constant speed. It also does it when just starting to accelerate. When cruising it will do the miss, stumbling thing and if I give it a bit more gas it will smooth out until the speed reaches wherever the throttle position is and then it will start stumbling again. I don't get it.

It was idling really high, like 1.5k-2k rpm (bad IAC) but now at idle
it sounds almost like the cars timing is way off. It stumbles and
misses and idles at a more normal RPM

I checked my codes and got the IAC and speed sensor. My speed sensor doesn't work right now cause it pulled out of the speedometer in the dash during the clutch install.

I then did a D-check and got the speed sensor and purge control solenoid, 33 and 35.

I checked for vacuum leaks, I checked connections, I even tried
unplugging the O2 sensor and everything. I'm at a loss. It's much
worse since the clutch install so I'm thinking that the LW
flywheel may have made the problem more pronounced or something.

Any thoughts or ideas?

subject edit by jason

Post by **Legacy777** » Sun May 22, 2005 4:04 pm

I've got both....granted I'm still n/a. The only thing I can suggest is to reset your ECU. If it was used to things with the heavier flywheel that could be affecting how it's running.

I did notice on my car when I reset the ECU the idle would drop real quick and sometimes lower then it should. It seems to have gotten better with some mileage on it. It's not perfect, but oh well.

legacy92ej22t · Post by **legacy92ej22t** » Sun May 22, 2005 5:31 pm

Well, my battery was unhooked for around 3 days when doing the install so I would think thetr ECU would have been reset.

I noticed on my way to work today that what it is is that is seems like the the problem is whenever the engine is running on vacuum. As soon as it gets positive or even pressure it runs smooth. WTF?

dumbskate · Post by **dumbskate** » Mon May 23, 2005 1:48 pm

i would look at how your battery earth is looking.

i had a very similar problem where the car would idle pretty shit and with my worn clutch, everytime i would let the clutch out in first it would buck and stuble making it feel like it was the clutch playing.

well i had the clutch replaced and it still did the same thing. so for totaly different reasons, one day i did the earthing mod and just moved my negative to a new spot on the guard with a cleaner surface.

from the minute i started it up every gear change was smooth as silk with none of the old syptoms.

what i put it down to is a weak or inconsistant spark which when only under light load(say idle orgoing into first gear) the extra load cuases the fuel mix to burn poorley giving the jerky feeling and the exhaust pops.

it could also help your ecu if thats getting funny signal by cleaning up the current it uses.

keep us posted

vrg3 · Post by **vrg3** » Mon May 23, 2005 4:42 pm

It seems to me that a lighter flywheel would certainly aggravate any driveability problems even if it didn't cause them, since the rotational inertia of the flywheel is responsible for smoothing stuff out.

This is so weird. The behavior you're describing is, like, the opposite of what my car was doing when I had an intake fitting loose. In this picture:
http://www.graphics.cornell.edu/~v/pics ... onator.jpg
I had the hose clamp on the right loose for a little while. It worked fine most of the time, but when I changed the throttle position quickly or tried to accelerate hard, I guess the engine would rock a little and create an intake leak, screwing up air/fuel mixtures until things settled back down.

It's just so weird that the problem would appear only when cruising and not when accelerating.

I guess the oxygen sensor is one device that's only really used when cruising and on vacuum. When you unplugged the oxygen sensor, did you reset the ECU too?

legacy92ej22t · Post by **legacy92ej22t** » Tue May 24, 2005 12:34 am

I unhooked the O2 sensor but didn't reset the ECU yet.

I checked all my hoses and everything seems tight and good. I am getting the #35 code in D-check though. Could a Purge Control Solenoid that is stuck open cause this severe of a drivability issue?

My speedometer cable is unhooked too, so the Speed sensor isn't getting a signal. That couldn't be causing this kind of problem though could it?

I'm seriously about a CH away from parting out and calling it quits.

Bosco · Post by **Bosco** » Tue May 24, 2005 2:38 am

My SS Ran like total poo when I had the speedo disconnected for a couple days. stumbling and stallling quite often.
I could only drive a few minutes (like 5 or 7) before it would give me cels and stall out a stop signs.
Is there a reason you have it disconnected?

greg donovan · Post by **greg donovan** » Tue May 24, 2005 2:45 am

Bosco wrote:My SS Ran like total poo when I had the speedo disconnected for a couple days. stumbling and stallling quite often.
I could only drive a few minutes (like 5 or 7) before it would give me cels and stall out a stop signs.
Is there a reason you have it disconnected?

well that sounds like the cause right there.

i wonder why?

douglas vincent · Post by **douglas vincent** » Tue May 24, 2005 2:50 am

I think the speed sensor is part of the load calculations.

dzx · Post by **dzx** » Tue May 24, 2005 3:38 am

I dont have a problem with mine, however i have heard of using too light weight of a flywheel with a lightweight pulley causing the timing belt to jump a tooth but not on our cars specifically. I dont think what your experiencing is caused by the lightweight accesories tho...

When i put the new engine and rebuilt tranny into my car recently i forgot to connect the speedometer so i drove around for a while without it. Car didnt have a problem but the ecu had been reset so who knows.

vrg3 · Post by **vrg3** » Tue May 24, 2005 6:36 pm

You could try just unplugging the little vacuum hose on top of the throttle body, capping the nipple and plugging the hose. That'll eliminate canister purge and reveal whether there's a problem there.

The purge control solenoid is one thing that changes when you transition from vacuum to boost...

I don't understand why a missing VSS would make the engine run so badly... I thought the purpose of the VSS was primarily to help in radiator fan control and to regulate idle speed to maintain power steering.

legacy92ej22t · Post by **legacy92ej22t** » Tue May 24, 2005 7:09 pm

OK, I went and had my speedometer cable replaced (I broke the original during the clutch install it turns out) and when leaving the shop it still drove like crap. Pulled over and reset the ecu and low and behold it drove much better. I did a D-check and got the all clear, not even code 35, purge control solenoid.

It did try to start stumbling again a couple times but smoothed out so hopefully it will be ok now. My filangies are crossed!

vrg3 · Post by **vrg3** » Tue May 24, 2005 7:16 pm

skid542 · Post by **skid542** » Tue May 24, 2005 10:07 pm

legacy92ej22t wrote:My filangies are crossed!

Don't think I could put it better....

Post by **Legacy777** » Wed May 25, 2005 4:21 am

Yup....the ECU not getting the VSS will cause very weird things to happen. You'll be fine.

BAC5.2 · Post by **BAC5.2** » Wed May 25, 2005 3:53 pm

Isn't that what I said on the phone the other day?

VSS is used for closed loop operating, which would cause issues when on anything but vacuum.

legacy92ej22t · Post by **legacy92ej22t** » Wed May 25, 2005 4:48 pm

Running on vacuum was the only time I was having the problem though. It ran good on boost.

But yes, you did express that you thought it could be the VSS.

It still feels like the engine is missing though at times and every once and a while it still acts like when the VSS wasn't working. I think there is another issue at play here too.

Still, that being said, it is driving much better then it was.

BAC5.2 · Post by **BAC5.2** » Wed May 25, 2005 5:27 pm

Lol, I meant when on anything but boost.

Project_Legacy · Post by **Project_Legacy** » Thu May 26, 2005 12:50 am

hmm i had a problem like this with my N/A. maybe you should get new spark plug wires. that fixed my problem. LoL.

Seriously tho.

legacy92ej22t · Post by **legacy92ej22t** » Thu May 26, 2005 1:06 am

Ya, my plug wires are pretty new but I should probably get some nice Magnacores. I really want a MSD-II ignition system too.

Tleg93 · Post by **Tleg93** » Thu May 26, 2005 5:54 am

legacy92ej22t wrote:OK, I went and had my speedometer cable replaced (I broke the original during the clutch install it turns out) and when leaving the shop it still drove like crap. Pulled over and reset the ecu and low and behold it drove much better. I did a D-check and got the all clear, not even code 35, purge control solenoid.

It did try to start stumbling again a couple times but smoothed out so hopefully it will be ok now. My filangies are crossed!

Where did you have it fixed at Matt?

legacy92ej22t · Post by **legacy92ej22t** » Thu May 26, 2005 6:06 am

Williamsport Auto, Joel did it.

dzx · Post by **dzx** » Thu May 26, 2005 6:34 am

I like the msd ignition

Tleg93 · Post by **Tleg93** » Thu May 26, 2005 12:49 pm

legacy92ej22t wrote:Williamsport Auto, Joel did it.

How much did it cost you?

legacy92ej22t · Post by **legacy92ej22t** » Thu May 26, 2005 2:36 pm

About $35. That's the part and labor. Not bad IMO.

I found out though that I have to have a working horn to pass inspection as well as a working blower/fan.

My horn won't work with the aftermarket steering wheel for some reason (not sure why) so I can either reinstall my OEM wheel for ispection and then swap 'em back or I need to hard wire a switch for the horn (preferred).

The fan problem isn't the blower motor or the thermostat part that is right next to the blower because I tried swapping them out and it didn't help. Joel said that there is a relay up under the drivers side dash or something that is most likely the culprit.

*sigh* It just never ends.....

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negative symptoms of LW Flywheel and crank pulley?

negative symptoms of LW Flywheel and crank pulley?