I bought a 96 Firebird Formula a couple weeks ago, and it's been nothing but a nightmare. I traveled 800 miles to pick the car up, and had to put $500 in it (water pump, plugs, wires, cap+button) before driving home. The plug wires kept burning on the headers, etc. Now, everything seems to be straightened out, but the car still runs like crap.

When I first try to start the car, I have to crank it for a couple seconds, let off the key, and the crank it again to get the engine to start. I'll allow the engine to build up oil pressure and then try to give it gas, and it cuts out throughout the RPM's. If I try to push the gas pedal all the way to the floor the engine wants to die. Sometimes, I have to crank, let off, crank, let off, crank, sputter sputter, crank and it will take off. Idles fine, no codes.

All in all, the car doesn't run like a modified LT1. It has, as far as performance mods, Edelbrock TES headers, new ??high-flow?? cats, MagnaFlow cat-back exhaust, K&N FIPK, Hypertech Power Programmer, Accel Extreme 9000 plug wires, and NGK Iridium IX plugs, ?rebuilt-new? A4 with a B&M shift kit. The radiator, thermostat, and harmonic ballancer were replaced before I bought it, and I've since replaced both radiator hoses (they both exploded on me). Also, the radiator cap looks to be a regular, plain old radiator cap. I can bleed the cooling system, and get the low coolant light to go off until I take it for approx. a 2 mile drive, then it comes back on...go home, re-bleed, refill, and same thing...2 miles it comes back on...go home, etc. etc. It's always on. Doesn't really seem to lose too much coolant unless I set the cooling fan temp back to stock, then the car overheats...otherwise, it stays around approx. 170 and doesn't overheat. This pretty much sums it up, but there's a story below if anybody feels like reading. Thanks ahead of time.

Well, I decided to take it to a shop with a MODIS or equivilant diagnostics computer while my girlfriend was at the dentist today. I was in a near-by town that I'm unfamilliar with the shops, so I stopped by Advance Auto Parts to ask if they knew of any high-end shops that would have this computer. The "woman" told me that any shop in town should have one.

So, I went to the first shop I saw, and asked if they had a diagnostics computer...again, the "lady" mechanic told me they could only hook it up if it was throwing a code. I told her it wasn't throwing any codes, that I needed a shop with a diagnostic computer that would give live sensor readings. She advised me that only a Dealer would have a computer any more sophisticated than a code puller, and it would only give more advanced code reading..so yeah lol

Well, I decided to drive to a used car dealership and ask for a recommended shop...the dealer was renting the garage-half in the back of his dealership to a mechanic and told me this mechanic would have the right computer to do the job. When I met the mechanic, I was taken aback. He wasn't wearing a shirt, had a beard & mustache, and had his left nipple pierced. Alright, well I figured he might know his stuff, so he told me to pull the car in and he'd hook it up to his computer. It wasn't a MODIS, but the lower end snap-on scanner with the roll **** and the YES and NO buttons.

Anyway, I pull the car into the garage. He was walking to the car with his scanner. I told him I needed to remove the Hypertech Programming so all the parameters would be what they should be -- he told me I didn't need to, but I knew better, and already hit the Start button to put the car back to stock before he could try to sway me any other way. As the programmer was doing it's thing, I was telling the guy my situation, about the previous codes that I had corrected (P0300, P0306, P0307) and told him I thought it might have a slight head gasket leak between 3 & 5, but not bad enough to come out the exhaust or into the oil. He told me he had a 99 Firebird. I asked him if it had the LS1 in it, and he didn't answer.

Well, after the PCM was back to stock, he proceeded to hook up his scanner. He was bending down looking at the sticker on the door, and fumbling with his machine, and kept asking what year the car was (after I'd told him it was a 96 repeatedly). Anyway, he drove it around the parking lot outside, blah blah blah. Came back in and told me it was running like it had a bad head gasket.

He told me to pop the hood. I did. lol He looked into the engine bay and informed me that I had an LS1! I said, "No, it's an LT1. They didn't use LS1's in f-bodies until 98." Nope, it's an LS1. Alright man. You win. His nephew has a 99 and my car has the same engine as his nephew's car. But earlier it was his..anyway, he just did a head job on his nephew's car a month ago and it cost $250 for parts. He said if I bought the parts, he'd do it for $250...so $500.

Not a bad price, I don't guess...I did check on the head set and bolts today...$261 and some change, but I don't allow anybody to work on my stuff lol I just wanted an opinion on why it was running like it was. He didn't check the fuel pressure...didn't check the compression, and didn't do a leak-down test on the cooling system.

I wanted to get out of there as quickly as possible so I didn't install the programming. Drove up the road to the dentist's office and my girl was just getting out. So, I figured I'd just wait til I got home...the car heated up more than usual...ran like TOTAL CRAP, and then overheated, blew out a little over a gallon of water. I stopped, reprogrammed the PCM, and filled the radiator with the purified water I carry in the trunk lol

I'm pretty sure the car needs head gaskets anyway, but I just want to get it running right before I keep putting more and more money into it. I have no problem buying and changing the head gaskets, but I really hope this fixes the problem. I mean, I bought a 94 Z28 T-Top 6 speed a week before the Formula. Didn't get to drive it until last week, but after I put the opti and water pump on the Z, man it SCREAMS. It's just wicked...bone stock, and wicked. The Formula has a higher factory HP rating and some decent bolt-ons, and runs like a pathetic little 4 cylinder.

Thanks for any help,

Paul

 

blown head gasket is my guess too. dont let him touch it if he doesnt know what hes working on. Pay the money and get it done right or do it yourself so you wont be kicking yourself later when he screws it up more and runs off with the cash

 

Let us know where you are located and someone local can reccomend a shop hopefully.

 

I'm definitely going to do it myself... I just thought it was funny that this redneck offered to do it for $250...and he thought he was working on an LS1 lol and the lady mechanic who tried to argue with me that code scanners were the only thing out there to read a PCM/ECM. and she offered to hook it up anyway and charge me $25 lol Said she might be able to get it to throw a code...I told her I had a code scanner in the car. I had a chance to buy a MODIS about 6 months ago for $5,000 updated in mid-2005. But...hard to spend that kind of money on it unless I actually start doing more mechanic work for somebody other than myself.

I was really just wondering if a head gasket would cause the car to run the way it is. I've never really encountered a vehicle with a phantom head gasket leak, that I know of. I mean, the last LT1 I changed the head gaskets in was my 95 Z28, and they were gone, and gone fast. There was no mysterious leak, low coolant light, etc. I had a funny tach for a while...then all the sudden, bam, water pump went out, temp gauge went to red, and there was water in the oil. I had the heads milled, new head gaskets, changed the oil, new opti, water pump, and timing set...left the bottom end alone under my girlfriend's dad's advice, and spun 2 mains and a rod 100 miles later. So...all over again, and then some.

I just hope after I put the head gaskets in the car it runs like I expected it to when I bought it.

Thanks for the replies,

Paul

 

If ya do the gaskets DO NOT do a valve job if the car has over 75,000 miles on it. Only do any valves that are burnt or leaking bad.

If ya do a complete valve job it is subject to start changing it's own oil(burning it and smoking like it is burning soft coal).
Check for leaking valves by pouring solvent into the ports for 20 min or so.

 

thanks 1racerdude. Hopefully I can get away without doing any of them. I just want to get this thing fixed so I can sell it.

Another thing I just noticed, though, but I doubt this is the problem, but maybe?? The large vacuum line running to the opti...the one that connects to the cap, is missing. It wasn't there when I changed the cap/rotor, so I just assumed the nipple was a "drain." I had put an opti on a 94 only a week before, but it was unvented, and it's been 3 years since I put the distributor on my 95 that I completly forgot how everything went. I was searching through some threads and found a link to the vacuum diagram on shoebox's website...I'm missing a vacuum line. I just went out and checked it out and somebody has cut the line right about at the coil and put a screw in it.

Also, I only changed the cap and rotor. The optical sensor was covered in oil that made it's way through the timing cover seal. I wiped everything down, but?

I also read that after 100K miles, the bearing in the opti unit can go bad and cause a vibration that will throw off the optical sensor's reading, and cause it to miss without throwing a code.

These damn cars are so frustrating lol

 

I know exactly where you are coming from LR, but I have had really good luck with high miliage late model motors and new valve jobs...seems that the newer ring packs don't suffer from that problem as I have had 8+ in the last year on just LT motors that were fine with between 100k and 140k on the clock. Have you actually seen this on LT1's?

 

Well they ain't a '55 where a screwdriver,pliers,and hammer along with bailing wire ya could fix most anything to get it going.
Not today-- ya need a "s" pot full of special tools and a grocery sack full of expensive parts just to do a tune up.

 

Yep
LS1's too.
They were rode hard and put up wet cars though.
Depends on if they have been run hot and all the moly is in the pan too.

 

That sounds like fuel pressure ...

 

Agreed, slap a fuel pressure gauge on that thing. Should be 40-42 psi with the key in 'on' after it primes up.

 

hooked up the fuel pressure gauge finally. Kicked the key on, and it built up to 11-12 PSI, unhooked the vacuum to the reg. and fired it up, read 21-22 PSI, hit the throttle from under the hood, and it didn't change.

I already bought a fuel filter for it, so I'm gonna slap that on and see if it corrects the problem. If not, guess it's probably the pump.

 

I would also check the injectors.

 

Maybe, but it didn't bleed off any pressure when I shut the ignition off. I'm gonna put the filter on in about a half hour, so I'll post back with the results.

 

new filter, same problem. I think it was the factory filter though...it an oem p/n on it, but maybe not. but...it was full of brown gas. After putting the new filter on, I cycled the switch on and off a few times to refill the lines. The pump sounded fine on the first cycle, but slowly got weaker with each cycle thereafter. The pump doesn't even sound uniform...I mean it sounds like the speed of the pump is fluctuating, and it gets slower and slower the more pressure it builds...and it's starting hard all over again.

I walked from the Formula to my 94 Z and cycled the key on it...same strong sound every time.

Pump or something else?

I was searching through some threads and ran across some talk of a "trap door" for removing the fuel pump. Was wondering if anybody knows of a write-up with pics of exactly where to cut the hole, or at least describe it. Thanks ahead of time