Help! Getting surging at steady throttle.
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Melting Slicks
Joined: Dec 2004
Posts: 3,049
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From: The second childhood is the best one of all.
Help! Getting surging at steady throttle.
I put a Halltech Tric intake on my car a couple of weeks ago. It's a 2002 Coupe. No other engine mods. I haven't gotten any codes or trouble alerts. The car idles well, the acceleration is good, everything else good. But when I'm driving at a steady speed, on a level road, I can feel the car surge or hesitate just slightly. I was carefull with the MAF and I don't believe I damaged anything. What could cause this?
Instructor
Joined: Jul 2005
Posts: 122
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From: Raleigh NC
Same problem for me, Except with the Blackwing
I too had that surge at cruising speed with the cruise on. Fairly level and it would sure up some then let off. I did (still) have problems with the idle. My idle on startup was fine, but once driving and coming up to stop sign, i'd engage the clutch and take it out of gear and the rpms would drop to 300 or 400 and bounce around between 400 and 600 for a while. It even shut off on me a few times. (embarrassing) I tried everyone's suggestions and didn't work. Tightened all hose clamps, "idle relearn", look for leaks. So I put the stock setup back on and it works fine. Im going to take it to a local tuner next week and see if he can diagnose what is going on. Let me know if you come up with some solution.
Ed
Ed
Burning Brakes
Joined: Aug 2000
Posts: 1,218
Likes: 1
From: MD
I had the similar problem early this week. It would hesitate upon acceleration, had irratic idling down to 400 or so and sometimes nearly stall. It also had the surging problem at constant speed.
I have the Halltech Tric as well. It turns out that one of the hose clamps loosened up and the seal re-positioned itself so that there was a gap. This caused a vacum leak.
I corrected the problem and those issues went away.
I am going to agree.... Vacum Leak.
I have the Halltech Tric as well. It turns out that one of the hose clamps loosened up and the seal re-positioned itself so that there was a gap. This caused a vacum leak.
I corrected the problem and those issues went away.
I am going to agree.... Vacum Leak.
Melting Slicks
Joined: Oct 2003
Posts: 2,077
Likes: 334
From: Dallas TX
St. Jude Donor '06-'09,'22,'25
Mine has done the same thing since I put my Vortex on over a year ago. No other symptoms except a surge at constant speed, and only in OD, not third. I don't think it can be a vacuum leak because it goes away when I put the stock setup back on. I've replaced the MAF and put on a ported/polished TB (not because of this), and I have the same surge. I'm guessing that some base tuning parameter needs to be changed.
Team Owner
Joined: Mar 2001
Posts: 21,325
Likes: 3,841
From: small town in S.E Pa. PA
St. Jude Donor '03-'04
combustion is a product of spark, fuel, and air. The variables for spark will not usually make this surge effect. Fuel surge would be a pressure issue, or the lack there of.. with a 60:1 air to gas ratio, air is usually the culprit. Vacuum is usually the reason for the inbalance... the other reason is a poor design in the air flow delivery system.. that is... turbulence. If turbulence is formed in the air delivery system, fuel and air mix can not be delivered consistently.. the result is surge.
Thread Starter
Melting Slicks
Joined: Dec 2004
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From: The second childhood is the best one of all.
Originally Posted by Evil-Twin
combustion is a product of spark, fuel, and air. The variables for spark will not usually make this surge effect. Fuel surge would be a pressure issue, or the lack there of.. with a 60:1 air to gas ratio, air is usually the culprit. Vacuum is usually the reason for the inbalance... the other reason is a poor design in the air flow delivery system.. that is... turbulence. If turbulence is formed in the air delivery system, fuel and air mix can not be delivered consistently.. the result is surge.
