92 rs with a swapped crate 350 I just changed the fuel system to a fitech self tuning efi system
i just finished this swap and one of the injectors went bad at the end of the first 5 mile drive Finally they warrantied me a new one. Was missing from foul plugs of course and a burnt wire.
changed the wires and plugs now it’s shaking the whole front end, everything is new. Hei dist, new motor mounts, copper core accel plugs and matching wires. No misfire but lots of shake upfront. Thought I had it off time but I threw the light back on it and retimed it. No matter which way I went it kept shaking. Any help appreciated boys A 3 year project that was supposed to be done 6 months ago. Seems every time it’s something else from a damn motor swap to efi I’m losing my mind. Thanks again guys

 

Have you double checked your firing order, or just made sure wires are all to and from the correct locations? 99.9% of the time you see a problem pop up right after you do work, the problem is with that work. If that is good, is the shake only present when idling or does it get better/worse with rpm? Are you down on power? Is it able to drive at all?

 

okay so I have checked the firing order. I’m wondering if I’m still wrong in it but when you press on the gas it smooths out easy
Haven’t driven it yet but doesn’t seem down on power. I also have it set at 9 degrees timing. If that helps. I did an hei dis swap from comp control to vacuum advanced and I’m wondering if they are off. My problem is figuring out which post on the dis would be number one. Wondering if I may have set it on 2 or basically one to the left or right of correct timing order. But every time I look at it I feel it’s right but something tells me I’m wrong. Thanks again. also tried every advance/retarded degree you can. Nothing made a difference. Just continues to shake any help is appreciated. I’m stumped to the point I’m about to check the motor mounts.

 

As the factory assembled the motor, the #1 post is at the front, just to the driver's side of center. If you put it back like that the plug wires will lay in place better than any other orientation, but it ultimately doesn't matter to the way the engine runs. As long as the rotor points to the right plug wire when that wire's cyl wants to fire, life will be good. If ugly maybe.

I completely agree with the firing order as a likely cause. It's SOOOOOOOOOOPPPPPPPPPPPPPER EEEEEEEEEEEEEZZZZZZZZZZZY to get 8 & 4 crossed, or 5 & 7. I'd suggest that you take all 8 plug wires off, and put them back on one at a time, NOT jam all 8 in the cap and "route" them or pork all 8 onto the plugs and "route" them that way either; take all 8 off, and start with #1, and ONE AT A TIME, install them so that they are KNOWN to be on the right plugs. NOT "look"; NOT "check"; NOT "I'm sure"; NOT NOT NOT NOT NOT NOT NOT NOT NOT NOT NOT NOT . PUT THEM from the right terminals to the right plugs, one at a time, one end to the other, one at a time. One at a time. Oh, did I forget to mention, ONE AT A TIME? In case I forgot, the way to do it is, ONE AT A TIME. #1 cap terminal to #1 plug, with NO other wires present; #8 terminal to #8 plug, with NO OTHER WIRES PRESENT, except the #1 that's already there; and so on, all the way around the cap. Just like I used to train people that literally came off of cotton fields into my factory where we wired up assemblies that had THOUSANDS of wire EACH: wire goes from here to there; if you are running a wire, and the place you get to already has a wire, STOP, because YOU JUST EFFFFED UP something; we supplied a list of terminals that should have no wires at the end, and if you wired the whole thing and didn't encounter a wire already on a terminal, and at the end all the terminals that were supposed to be empty were in fact empty, you could be DAMN NEAR 100% SURE you had eon your job right, even before any kind of electrical "checking".

At the same time, tuning problems can PERMANENTLY destroy spark plugs in a matter of SECONDS. So, put NEW plugs in before you try to start it when you do the wire connecting exercise. NOT "check"; NOT "clean"; NOT "look at"; NOT "they're new"; NOT NOT NOT NOT NOT NOT NOT. Swallow your pride, whup out yer wallet, buy a set, grow a pair, put in NEW ones.

I haven't been doing this for quite a half century yet, but only a few days to go before I can make that claim. Yeah I'm stupid, yeah I fart dust, yeah yeah yeah yeah yeah yeah; but at a certain level, seeing the SAME THING happen to young people just starting to learn this hobby, TIME AFTER TIME, starting in the 60s, ... I'm pretty sure that's the first "solution" step you need to take.

 

 

Since you have basically a completely new ignition system, newly installed and running (albeit like crap) the low hanging fruit is crossed wires. Mounts won't cause a shake so that's not an issue. I second sofa's advice on wiring from the start, one at a time, so you know for an absolute fact the wires are correct. Let us know what you find.

 

You were eighth gentlemen! Have new post if you’d like to check it out. Thank u so much!