I have a 1999 coupe with the following mods: Kooks LT Headers, VaraRam, B&B PRT cat back. I had the car dyno-tuned by A&A about 5 years ago when I had the Headers installed. Lately I have noticed sub-par fuel mileage (15 city, 24 highway) and “pinging” at high rpm’s. I am considering having it tuned again. The “pinging” really bothers me. What would cause the car to run like this? Do tunes need to be updated over time? The car is not my daily driver; however I have been driving it more frequently as of late.

Other than that, the car seems to run smooth and strong. If I do have the car re-tuned, would you guys suggest upgrading the intake to an LS6 version? I don’t want to do a cam or heads, as I want to keep it smog safe. Any other suggestions?

Also, I live in Huntington Beach, CA and I am looking for a shop to do this work. I read about CMS in Murrieta, but they are quite a ways from me. Are there any other shops in the OC area that people recommend?

Thanks in advance…

 

Go to Ryne at CMS. You`ll be glad you did!

 

I've heard nothing but good things about him.

 

Pinging= danger......... What fuel are you using? You might also try seafoam treatment right befor oil change. Sounds like carbon buildup to me. Do you use a catch can?

 

I religiously use Chevron 91 octane.

I do not use a catch can.

The car has 81K miles and I have never done any sort of fuel system/engine treatment...like seafoam.

 

I would do a search on here on seafoam. And catch cans. The ls1 builds alot of carbon deposits and i think it mabey your issue. its a simple inexpencive fix if the seafoam works. I use it once a year. Please do not run the car very hard with it pinging though it can cause damage

 

Thank you paint-tech.

 

What style of catch-can do you recommend? There seem to be a few different ones out there.

 

I just ordered the Elite Engineering Catch Can. Should I perform the Sea Foam before or after I install the Catch Can?

 

A scan tool will tell you if the pinging you're hearing is actual pre-ignition. I've tuned cars that had 12+* of ignition retard (due to knock sensor) and I didn't hear any pinging.

It's unlikely you need a retune and more likely you just need a tune up. Perhaps a spark plug or spark plug wire needs replaced. Or, perhaps, you have a cracked valve spring. There really are too many variables. I suggest taking it to a qualified LSx mechanic for a look over, unless you enjoy tinkering with your car.

 

Seafoam first follow the directions on can and use the pvc to inhale the seafoam. I am not saying it will fix your problem but the seafoam will remove carbon from the top end. Its a cheap fix if its carbon build up. If it does not help then a good LS tech is needed. If the problem goes away then install the catch can to help prevent buildup.

 

I have herd some members that let it soak overnight also. in the general section there is a post now on seafoam. Good luck

 

I have been following the Sea Foam thread over in C5 General. A few years back I was going to try it but didn't, so I have some knowledge of what it does.

So, tell me if this is strange. After reading about catch-cans and the PCV system, I went out to look at my car under the hood. I notice that the PCV hose that connects to the intake manifold is disconnected and the port on the manifold is plugged with a rubber cap. I have had the car for 8 years now and I have never noticed this. So, I took the plug out and connected the PCV hose the proper way. I took my car for a few test runs on the way to work this morning and I don't seem to notice anymore pinging at WOT in 1st and 2nd gear. I will check again after work today, but it seems to run better. I don't know if there are any placebo effects are going on but I definitely didn't hear the pinging I did previously. Does this make sense?

I'm still kinda leery about using the Sea Foam treatment, so if the pinging is gone after I reconnected the PCV system, then I may just install the catch-can and be on my way.

 

I can't speak to the effects of the PCV hose being plugged/disconnected. I can completely agree with paint-tech with the possibility of carbon build-up. I went through the exact same scenario a year after my header install and carbon was the culprit. Seafoam and a catch can solved my issue.

Good Luck.

 

Well that is good to hear. Which catch can did you use?

 

Red Devil keep the pvc in opperation. Its up to you on the seafoam use your own judgment. I have been using seafoam in all my vehicles for twenty years+ And I have a fleet chevy 6l ls Iron block vans that de-carbon once a year. I would try the seafoam it can not hurt if you do not have smoke on restart then carbon wasnt the problem, but I would bet it will smoke wich means carbon is burning off. I do believe the pvc system is is needed for sure, Who was the last shop that worked on your car. I am wondering why it was plugged of in the first place. Some forum members think seafoam is a gimick I do not. I also use Tectron to help with sticky fuel gauge Big three dealers have been using it for a long while.

 

Thanks again for the info paint-tech. The last shop to work on my car was Orange County Corvettes (3 years ago) for a clutch replacement and A&A (in Oxnard) installed my headers and dyno tune about 5 years ago. I rarely take my car to shops for work. It really is strange that the port was capped off.

I believe you about the seafoam, and I will give it a shot. Living in SoCal, my neighbors are very close to me and I'm hesitant to have a smoking car for several minutes. I'll probably have to drive somewhere else to perform the seafoam treatment.

 

LOL Red Devil I lived in Riverside County many years ago So I know what your saying. Now My closest neighbor is more than a mile I love it. Good luck and happy vetting

 

I considered this too. The problem is that for the Seafoam to really work you should let it sit(soak) overnight. I had good sucess with this procedure. I used the bottle (non-spray). Connect a 2' piece of 3/8 fuel line hose to the port on the throttle body. Have someone else start the engine. At idle, barely dip the end of the hose into the can so the car can "slowly sip" the liquid out of the can until the engine starts to stumble. Repeat this and let it sip ~1/3 of the can in small increments. Then have the helper hold the rpms at 1500, Then stick the hose deep in the can. The moment the engine is about to die, shut off the engine. Soak for 6 -8 hours. Then light off the smoke show.

I purchased my catch can from Forum vendor CCA. Chip is a great guy to do business with.

 

Did you pour the remainder of the contents in the crankcase and fuel tank?