I have a 96 camaro that i bought off my buddy for pretty cheap. He had the motor rebuilt but when he got it back it has a bad shake to it now and of course he waited to long to take it back and the place went out of buisess... go figure. It shakes pretty bad in the higher rpms, I have checked the timing and plugs and wires but none of that helped. When i drive 65 it smoothes out. It doesnt have Check Engine light but it does smell slightly rich when its idle. Any idea on what to do. I just want some general ideas before i rip into it. Thanks

 

Does it shake at idle when the car is sitting still? Have you checked the fuel pressure, coil packs, no plug wires crossed? Does it have auto tranny? If so, when you are driving it and it is shaking, if you put it in neutral, does it stop shaking?

 

Just curious, What was the timing set to? You should get the computer scanned but it kinda sounds like broken tranny mount.

 

i double checked the wires and they were all wrong but i put them in the right spots and still it didnt fix anything. it is a 5-speed and when in neutral it still does it. camaro is new to me so i am learning on the job. How do i check the coil packs?

 

i thought it may have been a broken tranny mount to but its not. I was about to check the timing.

 

You can use a ohm meter and test the secondary by removing the plug wires and testing resistance across the top where the wires snap on, then turn the coil pack upside down and test the primaries. The secondary should read 5K to 6.5K and the primaries are .3 to .6

Also, if you have an extra plug wire and plug, you can unsnap the plug wire at the coil and snap on the extra with plug, ground it somewhere on the maifold or fender and have someone crank over the engine. Look for blue spark, if yellow, the coils are weak.

Just a thought! If it is a 3.8L the coil packs should be numbered 6 3 2 5 4 1. I actually had a coil pack that someone had used as a replacement that was numbered 1 4 and they had it cross wired.

 

Chevy numbers their cylinders different, so the cylinder numbers starting from driver are

1 2
3 4
5 6

and if you have the firing order correct try unhooking the battery for about an hour then reconnect then drive easily, that will reset the computer and for the first 15 miles the computer will relearn the motor(15 miles for rangers, I'm not a big Chevy guy.)

 

First off, these types for problems can be very hard figure out based on information in a post. Most mechanics use sound and feel more then any of the other of their senses to figure out what is wrong. So we need to rely totally on what we are told by the info in the post.

You said in your first post you checked your timing and it was OK. BS there is no timing to check and no adjustment to make. (unless you are reprogramming the computer or remachining the engine block to move the crank sensor) So now I ask myself did he really pull the plugs? Its starting to sound like a miss. A miss will almost always show up in a plug. A good mechanic can look a plug and sometimes see what is going on but even a newbee can see that one plug looks different then the other.

A motor with 2 wire cross will start but barely move. A car with more then 2 wire crossed will most likley just backfire and not really start. Crossing wires on the same coil should have no effect on the way a motor runs. A direct ignition system fires 2 plugs at a time. I had a GM engineer tell me one time that if you switch the wires every 30K your plugs will last longer.

So if I assume all the info you have given at this point is BS and that only info that is good is the discription of the problem The most common cause of this is the age of plug wires, they are getting very high in resistance. This can cause a coil to fail. The best fix would be New plugs, New wires and figure out which coil failed using spark tester and replacing that coil. Whenyou have the plugs out keep them in order and take Hi res pictures. We can maybe see if anything else is going on.

http://www.harborfreight.com/cpi/cta...temnumber=4424

Good luck, and no more BS if you want help

 

I'm sorry I actually didn't check the timing I don't know why I out that on there that's my bad. I checked all the plugs and every single one of them were wrong but some how it still started and ran but it still shaked... But when I put them in all in the right spots it mad absolutly no difference.. That's why I'm like WTF how can it still ran exactly the same even I put the plugs in the complete wrong order.

 

I agree with Gorn. Just make sure you are using the firing order for a 3.8 and not a 3.4 as they are different. Also make sure that if you are using individual coil packs and using the plug numbering on the coils, that the coils have not been moved around.