Belt slip and shuddering?

[cagefightmma]

WTF! On low throttle the car stutters a little then surges? At ever shift, not even at WOT, the belt has a distinct squeal. Out of the 1-2, 2-3, and 3-4 shifts it does this and when it does, the car momentarily shuts down for a millisecond, then surges? This only happened after the Edelbrock install? I bought a Roush tensioner this week and put it in today and it didn't help? Any suggestions or ideas?

 

[kenneth]

Plugs maybe.

 

[Simon]

Doesn't sound like plugs to me. SOunds more like a vacuum leak or a tuning issue. Most likely the latter.

 

[Anthony05GT]

I would tend to think the belt squeal is do to the engine stopping causing a reverse squeal rather than a engine overpowering the belt drive squeal if you get my drift. I guess I'm saying forget the belt drive and look into the tune or a cause for the loss of power at shifts. Has this car been tuned by a pro?

 

[cagefightmma]

1st JDM, then a local tuner here who only does mustangs. I'm gonna have to go back up there and have him check it out again.??

 

[cagefightmma]

It did this problem with both tunes (JDM & my local guy). Sucks, I just got everything finished up and ready to enjoy but haven't been able to shake this problem. Now it's going to snow here any day and the car will sit in the garage until spring. F&*#!

 

[projeremy]

I'm running the E-force with the 2.75 pulley, I know I'm getting belt slip, but it's never made any noise like this. Sounds like a tune issue. What's the fuel pressure doing? My car was acting real weird like this at first, the fuel pressures were low and didn't come up fast enough when initially getting back into the throttle causing the car to sputter. Found a competent tuner and I think my car runs better than stock now.

 

[navbtcret]

I am running the 2.75 pulley with an 18% overdrive pulley and I am getting little or no belt slip. If you are not using a Gatorback belt I recommend you get one.

For tensioners the Thumprr is the only way to go and the only that has proven to hold up. I had some belt squeal a while ago but it turned out to be the bearing in my alternator going.

Have you check your plugs? If not I pull them to see what is going on. Do you have wideband? It sounds like you may going lean or a vacuum leak somewhere. Doing some data logging is the only real way to see what is going on by you or get it back on the dyno and see there. Have your tuner take it for a ride on the street so he see, feel and hear waht is going on.

 

[cagefightmma]

I am running the 2.75 pulley with an 18% overdrive pulley and I am getting little or no belt slip. If you are not using a Gatorback belt I recommend you get one.

For tensioners the Thumprr is the only way to go and the only that has proven to hold up. I had some belt squeal a while ago but it turned out to be the bearing in my alternator going.

Have you check your plugs? If not I pull them to see what is going on. Do you have wideband? It sounds like you may going lean or a vacuum leak somewhere. Doing some data logging is the only real way to see what is going on by you or get it back on the dyno and see there. Have your tuner take it for a ride on the street so he see, feel and hear waht is going on.

I don't have a wideband...yet. I am going to pull some of the plugs today to see if any of them are fouled. As far as a vacuum leak, I have tripled checked everything and can't find one? A friend of mine told me that for 2 yrs. he had the same problem but it didn't throw any codes. He replaced the MAF sensor and that took care of everything. Has anyone else had this problem with their MAF sensor?

 

[cagefightmma]

I am running the 2.75 pulley with an 18% overdrive pulley and I am getting little or no belt slip. If you are not using a Gatorback belt I recommend you get one.

For tensioners the Thumprr is the only way to go and the only that has proven to hold up. I had some belt squeal a while ago but it turned out to be the bearing in my alternator going.

Have you check your plugs? If not I pull them to see what is going on. Do you have wideband? It sounds like you may going lean or a vacuum leak somewhere. Doing some data logging is the only real way to see what is going on by you or get it back on the dyno and see there. Have your tuner take it for a ride on the street so he see, feel and hear waht is going on.

On the Edelbrock S/C, there is one vacuum 3/8" tube that comes off the back side and it connects to the brake booster and that's tight, the other one is an 1/4" and is on the drivers side at the rear of the manifold and that connects to the furl pressure sensor and that one is tight as well. Does anyone know if there are any other vacuum hoses that I should be checking? I'm going to pull out a plug right now.

 

[808muscle]

I cant imagine having that investment and not running a wideband.

 

[Greg Hazlett]

Does Advance or Auto Zone carry Gatoback belts? What makes the Gatorback so much better than a Dayco, NAPA, etc?

 

[cagefightmma]

I cant imagine having that investment and not running a wideband.

Actually buying one this week.

 

[Riptide]

Get the innovate wideband. Best one on the market.

 

[cagefightmma]

Well it's definately not the plugs. Just pulled a few out and they look brand new. Since the S/C install, I have driven less than 100 miles and the plugs look like I just put them in. Re-checked all the hoses and clamps and everything seems rock solid? WTF! I wish my car would throw a code so i could find out WTF is going on!

 

[navbtcret]

Well it's definately not the plugs. Just pulled a few out and they look brand new. Since the S/C install, I have driven less than 100 miles and the plugs look like I just put them in. Re-checked all the hoses and clamps and everything seems rock solid? WTF! I wish my car would throw a code so i could find out WTF is going on!

If you had it dyno tuned recently get a hold of your tuner and get it back to him so he can fix the issue if it is in the tune which it sounds like it might be. There can be so many different things causing this, fuel injectors, fuel pump duty cycle being maxed, etc, that he should be able to data log everything on the dyno including your A/F and igure out what is going on.

 

[MLC40]

Does Advance or Auto Zone carry Gatoback belts? What makes the Gatorback so much better than a Dayco, NAPA, etc?

I have broken my share of belts and to me the Gates green HD belts are the best.

 

[Greg Hazlett]

Who carries the Gates green belts?

 

[MLC40]

Who carries the Gates green belts?

I buy mine at Rock-auto but I think NAPA carries them too.

 

[dysan]

After reading your post I would say that mine does something similar. If I don't shift quickly when under heavy acceleration I will get that hesitation before it goes back into boost. I suspect it's just the boost bypass releasing the boost and then closing again putting you back into boost. As for belt slip, I've got the 3" pulley with the stock balancer and I get zero belt slip and I have the Roush HD tensioner. I believe Edelbrock recommends the Gatorback belts and that is what I have for my 3" pulley.