I have just recently purchased a 1992 Camaro RS w/ the 5.0 TBI motor. It is an auto, and it has a "custom" exhaust (appears to be 3in pipe all the way through with a muffler under the passenger seat, and a split at the back behind the axle). There is a Holley air cleaner on top, but other than that nothing else done to it.

Here's the problem: From a dead stop, when you give it gas, it is slow as hell taking off. It takes a good while to get to highway speeds (I'm giving it a tune up come monday). When you're doing 50-60mph and hit it (to go around a car) the passing gear doesn't really provide the speed needed.

It shakes a little bit in the 50-60mph range, but vibrates a good bit at the 70mph area. I'm thinking a good tune up will clear alot of issues, but I was wondering if some of the TBI experts had some more advice (as far as why its so sluggish).

Sometimes when I crank it up, it'll have a really rough idle and try to die out... Give it gas and it'll come back to life. I just replaced the fuel pump relay this morning.

Any help would be appreciated.

 

I had a few of your problems in the past. I can only tell you that once I fixed all of this on my car it runs and rides like a new car at 144,000. Granted I only drive my car in the summer but still...

You are right about the tune up. It will pay to do one. Upgrade to the MSD ingnition wires at the same time and put in a new fuel filter. Put in a quality performance spark plug.

Don't be afraid to advance the timing to get a little better response in the passing gear. Just not too much. Gas is $4.00 and counting.

I also suggest this is a good time for an oil change. Personally I am using synthetic in both my '86 carb and '92 tbi.

Check you wheel balancing. Once all of my wheels were balanced and all suspension issues were settled I no longer had any shake at any speed. Check that trans mount to. Also I went to a new set of Goodyear Eagle GT II 245/50/16's, the original tire and size for my car. I now love my engine pickup, suspension, stance and ride.

Hope this helps.

 

Yeah, I was thinking of going to the 8mm wires, just didn't know what brand to go with. As for the fuel filter, what's a good name to go with? I had been thinking of using E3 plugs, or this other plug a friend was telling me about.... I can't remember the name right now..... I always use Castrol Sytnec... I've never had a problem with it.... The tune up will happen this friday.... As well as the oil change.....

I have to replace my tires tommorrow... I got about a half a mile from my house and heard that all familiar tire going flat thump, thump, thump.... I turned around and got back to the house to find that my dry-rotting tire had completely separated... So I'm getting another set tires tommorrow.

What's the normal 0-60mph time for these cars, stock?

Thanks for the info man! I didn't really think about tires not being balanced, but now that you've mentioned it, its missing a wheel weight or two.....

The help is much appreciated.

 

I used NKG Vector plugs...they are great....dealership told me the only plugs to use without getting a Service Eng light was AC...not true...

I have whatever fuel filter that AutoZone sells...no name brand needed for that...

and it sounds like wheel balancing will solve your shake, rattle and roll problem.

I believe most stock times start around 15.4...at least that is what I have read...lower is possible

 

NKG Vector's...... Hmm.... I'll look into them.... Do they require gapping?

15.4 huh? I'll have to work on that... I'm planning a 350 or 355 build/swap in the possibly near future....

A few machine shops around here have "abandoned" engines for sale that have been rebuilt, the owners just haven't paid for them.

Thanks

 

I have a 350 TBI that came in my car and let me tell you, a good tune up made a night and day difference on my when i bought it a few monthsw ago. plugs, wires, air filter, breather filter, pcv valve, cap rotor and fuel filter and injector cleaner. made it feel like I gained 15 horses. Don't leave anything out.

Lots of guys on here sing the praises of seafoam treatments, which do a lot more than a basic injector cleaner but I haven't tried it yet. Sounds like you should do one BEFORE you change your plugs and fuel filter.

I had some vibration issues and replacing my driveshaft helped. I still have a litle bit at highway speeds and I hear that aluminum driveshafts cure this problem. Again, i haven't done it yet, but you may want to consider that route.

At one point I also had a bad plug wire that caused a miss under load that I mistook for vibration at first. Just some things to consider. Good luck.

 

Idk much about the seafoam treatment... I'll probably hold off on that for a while... I am definitely doing the tune up friday or saturday though.

I have heard the driveshafts did cause vibration problems, so I have been shopping around for an aluminum one....

Thanks for the advice! I'll keep posting updates.

 

BTW, advancing my timing gave me some throttle response too. I'm at 8* right now. Gonna play around in the 5-8 range to optomize it, but after you tune it up and see how it tuns I'd try that. MIght wake it up a little bit.

 

Yes I gapped them at .35 the factory spec.

 

So after I do my tuneup, advance it a little bit huh? How much can I go and still not see too bad gas mileage? My car is gulping down the fuel right now, but that's cause it needs that tuneup.... I haven't been driving it the past few days.... Damn dry-rotted tires need replacing......

I think what I've decided is MSD 8.5mm wires w/ either NKG or E3 plugs, K&N Filter in the air cleaner, oil change with Castrol Syntec, then playing with the timing...

 

Sounds likre a plan...and you will know when the advance is right by driving the car...

 

A little update.... After popping the hood and starting to change the wires, I found out why my car was running like crap....... One of the spark plug wires had managed to touch the exhaust manifold and melted completely in half... Runs a little better now..... I just did the wires, I haven't put the new plugs in yet.... Will update as I can......

 

Just make sure to listen for knock if you advance the timing. You can proabably get away with 6* advance, but you might need premuim fuel.

For the spark plugs, regular AC delco's are fine. NKG is a great plug too, but IMHO save the money because AC works fine.

For the cap + rotor, try to get the duralast gold from autozone. Its got the nice brass contacts.

 

Another update...

I put in some Bosch Platinum 2 plugs.... But the wires managed to touch the exhaust again, so its back to running like crap...... I'm going to get some more wires, and re-route everything..... I've already bought some wire holders to help keep them together.....

Haven't had time to do the fuel filter yet...... Neither have I had the time to do the timing....

Did anyone else catch alot of hell doing their plugs? Had to go from underneath to get them done......

I also have alot of hoses disconnected I still haven't gotten straightened out... Could someone please post a pic of their stock engine bay? I'm curious to see the routing of these hoses, as well as the plug wires.....

Well, I've got a leaky water neck to take care of.....