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Discussion Starter · #1 ·
Ok here goes. The car has a miss above 3 grand as previously stated in the subject. When I first got it all back together there was no miss. The miss developed just before going to anderson's dyno. The car pulled good up untill 3 grand then it spit and sputtered all the way to 6. We regapped the plugs down to .30 and still the miss was there. I have checked the resistance on the wires and they are fine. I replaced the cap and rotor, and checked the coil's resistance, but this doesnt seem like a true test for a coil since I cant see what happens to it when its got full juice going through it. Its stock by the way. I thought maybe the TFI but the miss hasnt got any worse its just always at 3 grand. From what I've read if it was the TFI eventually it would get worse and just completely fail all together. So whats left is the distributor which is also stock. I just ordered a PS91 coil today but I dont really know if this will fix the problem. All mods are listed in sig. Everything else not listed is stock. Please help
 

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My 1st guess would b Plugs and/or gap still too wide...I would try that 1st..It's cheap and w/ ans the elect ?.A bad coil wire or not being properly connected(all the way in)can also cause a miss under heavy load....then go from there...
 

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My guess before reading your post was gonna be the coil. I'm still betting on the coil. With EFI it's a little more difficult to read the plugs for lean, but if you see specs in the porcelain, you may want to look into a fuel delivery issue.
 

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Discussion Starter · #4 ·
Well the plugs look fine no sign of spark knock or detination. I guess I'll just have to wait till the coil gets here sometime in the middle of the week. Thanks for the ideas guys.
 

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look into your mas, it might be dirty,
 

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Discussion Starter · #6 ·
Noels, another good idea. Ill check that 2. To clean the mass air, use alcohol and a q-tip? I'll do this as soon as it stops snowin. I hate IL.
 

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Yeah, I saw on the weather channel that you guys are getting hammered. I'm right at the very bottom of it in NW AR. We get lucky most of the time. Good luck with the car.
 

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Hey man, I had a simminlar prob and I chased everything!!!! It ended up being a vacume problem. I think that the only difference was that it happened at 25-2700 but under WOT it was fine. Good luck.
 

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Discussion Starter · #9 ·
Hmm well the miss goes all the way up after 3 grand. Another thing I forgot to mention is the miss is only there while in gear under load. Revs to 5500 without a problem out of gear.
 

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Discussion Starter · #10 ·
I'm pretty sure its not a vacuum problem it has 16-18 at idle, but then again I dunno what it would have around 3grand. I'm gonna go with it being something in the ignition because...well thats what danny at anderson said he thought it was. Im sure he has more experience than me with these things so until I can rule out the ignition as being the problem thats what I will look for. The coil should be here either tomorrow or thurs. Then I can rule out if that was the problem. Also I will clean the mass air before 2 make sure thats not it.
 

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The rason that I said vacume was mine did the same thing, only under load, I replaced the coil, wires, plugs, ignition mod, the distrib, tps senser, fuel injecters, and the fuel filter before I whent and replaced the vacume lines and as soon as I did that, Miss gone. I posted on here about the same prob and I got no answers. I sear that I was about to pull my damn hair out and I spent a little bit of cash just for it to turn out to be a vacume line. This may very well not be your problemm but it sure turned out to be mine. Good luck.
 

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Have you messed with the timing and forgot to plug in the spout connector? The reason I say this is I forgot one time and when I went for a drive the engine ran like crap above 3k.
 

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Hey Mikejb, How do you like that stealth intake? I am putting together another motor that will be carbed and I am considering using that one. Not trying to interuped the post but wanted to know. Thanks
 

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I love it. I gained 65 rwhp and 37 tq with it and the GT40 heads. :)
 

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I hope the coil fixes it for you... If it doesn't try (as stated above) checking for a vacuum leak.. pick up a can of starter fluid and spray it around the base of your intake... both were upper meets lower and where lower hits the heads. If your idle suddenly jumps a few hundred rpm you found a leak. If nothing, pull each vacuum line one at a time and see if you notice your idle drop (it should, if not thats your culprit), plug it with your finger and see if you idle jumps back up, then plug it back in. If nothing from that... perhaps your computer is wigging out on you. I've had short term vs. long term memory problems. Try adding 4 or 5lbs of Fuel Pressure and take it for a spin. If that does it pull your battery for half an hour or so to reset your computers memory.... then you may have this problem again and have to add even more FP. I've seen a setup similar to yours higher then stock compression with good heads/intake/cam/etc. using 30lb injectors he had to go around 50 to 55lbs of FP.
 

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Discussion Starter · #16 ·
Hey guys sorry I havent posted in the last few days.

Mike- Good idea but the spout is in there.

Well I would have changed the coil out but Fed Ex is 2 days late with my package. I hate Fed Ex. I have never had good service from them. They are always atleast 1 day late unlike UPS which is always on time. Anyways hopefully it will be here tomorrow when I get home. Hopefully I can get it out on the road after I get it in there, its been pretty crappy around here the last few days.

Slo5oh- Ill check again for vacuum leaks like you said. I doubt changing the fuel pressure would affect it though again im not sure. On the dyno the A/F ratio was adjusted close to 13:1. If all else fails Ill bump up the pressure a little bit and see what happens. Again thanx for all the thoughts guys hopefully I can figure this out and maybe this thread will help someone else out in the future.
 

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Have you run any codes. Check for a fuel pump circuit failure. My car was doing this and I replaced the fuel pump relay, under the drivers seat, and it worked fine. Down the road it started doing it again. I then replaced the eec relay. It has worked fine since.

On an older motor I had a bent pushrod that was causing a miss. I didn't find out that was the problem until it broke a valve spring.

Also, when is the last time you replaced the fuel filter?
 

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Discussion Starter · #18 ·
Well guys I think the coil did it. Finally got it today and put it in outside. Jesus it was cold, damn brother was usin the garage to fix his truck. Anyways I took it out and couldnt get it up in the RPM's at first cause theres still a lil ice on the road, but I hit another road and got it up to 5grand and it didnt miss a beat. Disclaimer: Never do this in an Illinois winter. Anyways thanks for the ideas guys hopefully Ill get another chance to dyno it soon. I hear theres new dynojet in Sprinfield IL now. Might have to check that out.Later
 
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