No "woosh" (LONG)
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Joined: Jan 2005
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No "woosh" (LONG)
I am trying to find out why i have a bad stumble in RPM's at idle and a slight bucking at speed. I have noticed that i have no "woosh" sound when i open my gas cap. I do have however 38 PSI whenever i turn off the key and it seems to hold pretty well while driving. I replacedthe fuel filter, plugs are recent, wires recent, new cap and rotor. checked timing but the darn dist. wont stay still no matter how tight i get the holdown clamp. As i rev it you can watch the dist. turn. not sure how to fix that as i have changed between a number of hold down clamps. Currently i have a code 15 (CTS as it is not there 
) and a code 33 (MAF it is flowing too much air with the ram air kit?) not any other symptoms other than hard starting first thing in the morning, bad idle, and a slight bucking while cruising. Anyone have any ideas? 
P.S. Just did a pressure test and over 15 minutes my pressure went from 38psi to nothing. Does this have anything to do with the vaccuum hose not being hooked up the the AFPR?
) and a code 33 (MAF it is flowing too much air with the ram air kit?) not any other symptoms other than hard starting first thing in the morning, bad idle, and a slight bucking while cruising. Anyone have any ideas? P.S. Just did a pressure test and over 15 minutes my pressure went from 38psi to nothing. Does this have anything to do with the vaccuum hose not being hooked up the the AFPR?
Last edited by Mtrhd329; Sep 18, 2005 at 01:10 PM.
Thread Starter
Instructor
Joined: Jan 2005
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Ok i figured out that my distr holdown clamp was a cheapo of the shelf model that somehow wasnt long enough to make full contact on the distr. Got a new one and the timing problem is fixed. However....the car still acts the same as before except it is now idling at about 700 vice 600. The timing is set to 16 degrees with the tan/black wire undone. (this is what my mechanic told me to run it as for the cam) Not sure what else to look for.
Team Owner
Joined: Mar 2001
Posts: 54,124
Likes: 30
From: Cincinnati, Oh USA
16 degrees is way too far advanced for a stock cam. You need to try decreasing the initial timing a little at a time and driving it. On a level road at constant speed, bucking is the clue that timing is too far advanced.
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Actually the cam is a TPIS ZZ-X cam. Not sure the specs but i was told to run 16 degrees for that cam. Should i set it for stock timing and increase until it detonates? It ran fine for a few months after i had it installed but now it is acting up 
Pro
Joined: Dec 2002
Posts: 603
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From: 84 383 XFire Chandler, AZ
Also check the harmonic balancer. Sometimes the rubber seal between the two pieces of metal will slip or break and cause the inability to set the timing properly. One way to check it is disconnect the EST and monitor the timing with a timing light at about 1500 rpm. If the mark holds constant you should be ok - if it moves around you more than likely need a new balancer.
I agree with everyone else that 16* too much at idle. I would set it to 8* or perhaps 10* and see how the motor likes it.
I agree with everyone else that 16* too much at idle. I would set it to 8* or perhaps 10* and see how the motor likes it.
Melting Slicks
Joined: May 2003
Posts: 3,490
Likes: 68
From: Hewitt NJ
Originally Posted by Mtrhd329
...P.S. Just did a pressure test and over 15 minutes my pressure went from 38psi to nothing. Does this have anything to do with the vaccuum hose not being hooked up the the AFPR?
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Update-
In checking out my timing something told me to check the rotor. The rotor was full of carbon and the button from the coil was not sticking down far enough to make contact
turns out my "mechanic" friend installed the rubber spacer before the button so it was spaced out the thickness of the spacer. swapped the two so it was correct and nowi have no more stumbling. 
I tried to reset the timing but my balancer keeps jumping around. is this a sign of a broken balancer? If so what is the difficulty rating on this. I can do this in the driveway with a puller right??
In checking out my timing something told me to check the rotor. The rotor was full of carbon and the button from the coil was not sticking down far enough to make contact
turns out my "mechanic" friend installed the rubber spacer before the button so it was spaced out the thickness of the spacer. swapped the two so it was correct and nowi have no more stumbling. I tried to reset the timing but my balancer keeps jumping around. is this a sign of a broken balancer? If so what is the difficulty rating on this. I can do this in the driveway with a puller right??