1994 Firehawk misfire/detonation

Post your comments & questions

Moderators: FAOA Administrators, FAOA Moderators

Post Reply
Firehawk197
Posts: 89
Joined: Sun Mar 15, 2009 6:00 pm
Location: Homosassa, Florida
Contact:

1994 Firehawk misfire/detonation

Post by Firehawk197 » Sun Mar 15, 2009 6:20 pm

I bought a Firehawk about 4 months ago and it ran really crappy because the water pump leaked on my opti so i changed both of them along with a new street fire coil. But ive only put about maybe 2k miles on the new opti and it has a miss or detonation problem. Ive tried little fix its here and there but am getting no where quick. Its almost like it is one cylinder doing it but no wires are arcing. I notice it more in the 2k - 3k rpm ranges but you can still hear it when you romp it. Any help would be great.
94 Firehawk #197 Daily Driver

No Blue Bottle, Just Balls and Throttle

User avatar
Scott Chab
Posts: 3309
Joined: Sat Feb 23, 2002 3:44 pm
Location: Wilmington, Delaware

Re: 1994 Firehawk misfire/detonation

Post by Scott Chab » Sun Mar 15, 2009 9:51 pm

If you didn't say that you replaced the opti I would have said that was the problem.

Can you get it scanned to see if there are any codes in the PCM?
'94 Hawk #110
Back on the road helping me make bad decisions again

Firehawk197
Posts: 89
Joined: Sun Mar 15, 2009 6:00 pm
Location: Homosassa, Florida
Contact:

Re: 1994 Firehawk misfire/detonation

Post by Firehawk197 » Sun Mar 15, 2009 10:18 pm

I am going to try to get it scanned tomorrow or tuesday, i dont have an SES light on but i know the guy that has the scanner that will tell me what or all cylinders that are loosing compresion/spark/fuel/air
94 Firehawk #197 Daily Driver

No Blue Bottle, Just Balls and Throttle

Chuck Stong
Posts: 315
Joined: Fri Mar 22, 2002 4:37 am
Location: Dallas, Texas
Contact:

Re: 1994 Firehawk misfire/detonation

Post by Chuck Stong » Tue Mar 17, 2009 5:16 am

also try using the stock coil. I have seen bad aftermarket coils that were weaker than stock, even though they were supposed to be better.
Chuck Stong
94 #307, 383 setup for roadracing and with an audiophile quality sound system

Firehawk197
Posts: 89
Joined: Sun Mar 15, 2009 6:00 pm
Location: Homosassa, Florida
Contact:

Re: 1994 Firehawk misfire/detonation

Post by Firehawk197 » Tue Mar 17, 2009 9:04 am

Yeah I'll put the old one back on there and see how it works
94 Firehawk #197 Daily Driver

No Blue Bottle, Just Balls and Throttle

Firehawk197
Posts: 89
Joined: Sun Mar 15, 2009 6:00 pm
Location: Homosassa, Florida
Contact:

Re: 1994 Firehawk misfire/detonation

Post by Firehawk197 » Wed Mar 18, 2009 5:39 pm

So I discovered the problem... at one point in time i blew my exhaust manifold gasket and it destroyed the porcilin on my #8 spark plug... car runs like a champ now
94 Firehawk #197 Daily Driver

No Blue Bottle, Just Balls and Throttle

JBPOLK
Posts: 34
Joined: Thu May 09, 2002 12:26 pm
Location: Newark, Delaware

Re: 1994 Firehawk misfire/detonation

Post by JBPOLK » Thu Jun 11, 2009 6:37 pm

I had serviced my opti-spark before putting the car up for storage. There are several items that you could check on. One would be the cable plug on top of the cable to the opti. It seems that you could have an intermittent on the "Hi-Res" signal output (1 deg.) signal. On top of the manifold about mid-center there is a jack/plug connection that can cause problems. I've seen this directly in my car;particularly because it was built in 1994.
If the car starts, but later on sputters I would trouble check that cable from the opti-spark back to the pcm.

Scott Chab you still here huh?. I haven't logged on successfully in a long time. I'm #067 on the Firehawk.org site. Formula FH with a 6.3 Stroker. Are you still in the Wilm. DE. area?. I'm overhauling Mz. Thing, and maybe I'll be finished before the Summer ends. Old #67 had been in the garage since 2006.
8)
1994 Formula FH, (Violet/Gray)
6.3Ltr Engine.
GM Performance Parts

User avatar
Scott Chab
Posts: 3309
Joined: Sat Feb 23, 2002 3:44 pm
Location: Wilmington, Delaware

Re: 1994 Firehawk misfire/detonation

Post by Scott Chab » Fri Jun 12, 2009 8:53 am

JBPOLK wrote:
Scott Chab you still here huh?. I haven't logged on successfully in a long time. I'm #067 on the Firehawk.org site. Formula FH with a 6.3 Stroker. Are you still in the Wilm. DE. area?. I'm overhauling Mz. Thing, and maybe I'll be finished before the Summer ends. Old #67 had been in the garage since 2006.
8)
Still here and still in Wilmington. I only put about 1000 miles on the Hawk last year so I think I might try to sell it.

What are you doing in the overhaul?
'94 Hawk #110
Back on the road helping me make bad decisions again

JBPOLK
Posts: 34
Joined: Thu May 09, 2002 12:26 pm
Location: Newark, Delaware

Re: 1994 Firehawk misfire/detonation

Post by JBPOLK » Mon Jun 15, 2009 6:07 pm

This has nothing to do with detonation. Scott I am hopefully completely overhauling Mz. Thing. I stopped on updating my front end with installing polyurathane inserts in my "A" Frames, e.t.c. I am going to do my sound system, and interior. My engine was overhauled when it got the 6.3Ltr. Spec parts installed so hopefully no updates there.
Now that GM is going into bankrupcy I figure I'll keep mine; considering it's a Classic.
Since the latest of our Firehaws are at best 7 years old by now there is no reason to keep her stock (IMO). Allstate Insurance ruined my car after an accident in 2003 and when it was repaired they used "Pontiac Parts" so my car is pretty unique now. I've got '97 taillights a '95 air dam, and the rear deck off of a '95 Formula. So all those posts about "It a real Firehawk" are over for me. I just enjoy a nice strong car (wi. sound) for cruizing and bruizing. I thought that I had saw your car down there in Wilmington last December. I was going on 95South off of Bankroft Parkway (near Penna. Ave.) and I saw what looked like a red Firehawk or T-Am heading south. Our cars are pretty rare so I thought that may have been you. I have a Ford Expedition that I am driving normally.
I intend to keep my "Bird" if possible. My first car was a 1970 Pont. Gran-Prix with the 455Cu. V-8 so I still appreciate the Pontiac Driving Experience.
Peace
8)
1994 Formula FH, (Violet/Gray)
6.3Ltr Engine.
GM Performance Parts

Post Reply