buckin problem

[blue87lx]

i recently put an offroad h on my car and now when im at a steady speed it feels like my car bucks/has a small miss. i checked all plugs wires and stuff. now the tube that comes from the hpie and connects in the engine bay i left disconnected. wouldl this have anything to do with it?

 

[my289eatsrice]

Yes, this is your EGR. You must connect this, especially if you need to pass emissions. This will control your idol at lower rpms up till 3/4 throttle, so at WOT, then it wont have any effect. See if you can reconnect this tube, and then you won't have any problems.

 

[jrichker]

Yes, this is your EGR. You must connect this, especially if you need to pass emissions. This will control your idol at lower rpms up till 3/4 throttle, so at WOT, then it wont have any effect. See if you can reconnect this tube, and then you won't have any problems.

This isn't the EGR. It is the Thermactor Air System or smog pump. It blows air into the cat converters to make them work. If you don't have cats, it is pretty useless.

The EGR system has a vacuum source (line from the intake manifold) that goes to the EVR, computer operated electronic vacuum regulator. The EVR is located on the back of the passenger side shock strut tower. The EGR valve and the passages in the heads and intake manifold route exhaust gas to the EGR spacer (throttle body spacer). The computer uses RPM, Load. and some other factors to tell the EVR to pass vacuum to open the EGR valve. The EGR sensor tells the computer how far the EGR valve is open. Then computer adjusts the signal sent to the EVR to hold, increase or decrease the vacuum. The computer adds spark advance to compensate for the recirculated gases and the slower rate they burn at.

Hving done my best to enlighten others, now for help in finding & fixing your problem.

Dump the codes and see what the computer says is wrong…

Here's the link to dump the computer codes with only a jumper wire or paper clip and the check engine light, or test light or voltmeter. I’ve used it for years, and it works great.

See http://www.troublecodes.net/Ford/
OR
See http://www.mustangworks.com/articles/electronics/eec-iv_codes.html

IF your car is an 86-88 stang, you'll have to use the test lamp or voltmeter method. There is no functional check engine light on the 86-88's except possibly the Cali Mass Air cars.

Codes have different answers if the engine is running from the answers that it has when the engine isn't running. It helps a lot to know if you had the engine running when you ran the test.

Trouble codes are either 2 digit or 3 digit, there are no cars that use both 2 digit codes and 3 digit codes.

For those who are intimidated by all the wires & connections, see http://www.actron.com/product_detail.php?pid=16153 for what a typical hand scanner looks like. Normal retail price is about $30 or so at AutoZone or Walmart.

Or for a nicer scanner see http://www.midwayautosupply.com/detailedproductdescription.asp?3829 – It has a 3 digit LCD display so that you don’t have to count flashes or beeps.. Cost is $35.

 

[JBeezy53]

I used heater hose as the tube from my x-pipe to my check valve.