Hi everyone,
Just finished up my car this weekend, and it still seems like it has a slight miss to it. We put new ac delco plugs, and wires, new distributor with msd cap and rotor, new water pump, and a new msd coil. It cruises down the highway just fine, but when i accelerate i can hear a miss in it. What do you all think? I checked all the wires to make sure they were on all the way, and it still has the slight miss. Any ideas?

 

What exactly is a "new distributor with msd cap and rotor"? You bought the back 1/2 from where? .... and then put an MSD cap/rotor on it.

What did you gap the plugs to? Are you sure the plugs are tight, and you didn't crack an insulator? Have you checked in the dark for arcing wires? Have the injectors been cleaned?

 

Re check the plug wires for the proper placement and the adjustment of the rocker arms. Might be just a misadjustment, or in proper placement of wires. Make sure that they are not contacting the pulley esp. on the passenger side.

 

I got the back 1/2 from autozone, it looked brand new and ran around $160. THe old back 1/2 was rusted awful lol, and the bearing was going bad i think. When we pulled the old stuff off, water came out of the cap!!!! Anyways, ill do some looking around on it, and let you know if i come across anything. If you have any more ideas, please let me know. Your help is greatly appreciated. Thank you

 

Unfortunately, many of the Opti rebuilds and auto chain replacements are not too reliable. The cam position sensor is in the back 1/2. Check for codes - particularly the codes for loss of low and high respolution pulses from the Opti (DTC 16 and 36).

 

Bingo, I'll bet that opti is garbage.

thepartsladi on ebay sells genuine delphi opti's for less than the taiwan refurb opti's autozone sells.

If it isn't plug gap, loose wire, or a wire sitting on a header and the MSD cap is fine, I would look toward the opti.

 

Also, you may want to check fuel pressure, replace the fuel filter, then check again.

 

i am a little confused about a few things here, please clear them up for us

when you say you just finished your car, what did you do exactly- just what you stated there or was there more to it

you say "still seems to have a slight miss" is is the same miss that you had before you replaced all of these parts? and is that the reason why you replaced them?

also i find it weird that you say you "hear" a miss, what exactly does it sound like and can you also feel it ?

and just to be clear. it only misses when you have a load on it, not at an idle or anything?

i know its alot of questions but it will help us to help you, it would also be a really good idea to put some information about your car in your signature along with any mods you have done to it