Installed New Walbro pump...car ran fine for 5 minutes then quit..wont start

[02z28ls1]

I would have to agree -the mechanic sounds like he is trying to send the kids through college at your expense there.Obviously the water pump is not causing the no start condition so tell them to wait on that until you get it running.They most certainly can scan for trouble codes without it running-but they want to run a scope on the ignition patterns it needs to be running-two different things.The plugs could be gas soaked from alot of things-but if it's not starting then they would be soaked with fuel from it not sparking.Does the engine have spark when cranking?We've established you have fuel pressure-the infamous optispark distributor is a known trouble spot.Yes you can foul out spark plugs and replacing them can sometimes get an engine running again w/o doing anything else-but check for spark at the plug first.

[Hamster Dance]

I would have to agree -the mechanic sounds like he is trying to send the kids through college at your expense there.Obviously the water pump is not causing the no start condition so tell them to wait on that until you get it running.They most certainly can scan for trouble codes without it running-but they want to run a scope on the ignition patterns it needs to be running-two different things.The plugs could be gas soaked from alot of things-but if it's not starting then they would be soaked with fuel from it not sparking.Does the engine have spark when cranking?We've established you have fuel pressure-the infamous optispark distributor is a known trouble spot.Yes you can foul out spark plugs and replacing them can sometimes get an engine running again w/o doing anything else-but check for spark at the plug first.

Changed 7 out of 8 plugs...I cant get the "infamous" #8 plug in the passenger rear, even had the car up on a jack and tried to go from underneath...NO POSSIBLE WAY to get to it...unless I remove the starter...
I just said fuck it and closed up shop...
plugs were pretty carboned up and had a combination of fuel and oil...
Tomorrow, I am going to change the oil and try to fire the son of a bitch up...what I am going to do different this time though, is not shut the car off and let it idle for 10 minutes, then give it some foot on the gas....
Best way to get any remaining fuel out of the intake I heard is to drive the car for 30 minutes at fairly high RPM's...to blow it all out the exhaust...but I am scared to get stranded somewhere if the car dies on me...
My only thought right now is, to check for a leaking injector...possibly dribbling fuel into the intake while the car is off...
How do I check for spark at the plugs? Can I just pull one at a time and ground it against the engine block and look for an arc?

[Hamster Dance]

Ohh, and the mechanic at the Tuffy said he scanned the car and it didnt throw out any codes...
If the plugs werent getting fire, (bad opti) wouldnt that show up?

[GEARHEADNATE]

Just because the engine won't start dosen't mean you can't hook up a scanner. My 98 drove it home from work, got back in the car 10 minutes later no start hooked up the scanner and it had a bad crank position sensor. So I would try hooking up a scanner.

[Hamster Dance]

Just because the engine won't start dosen't mean you can't hook up a scanner. My 98 drove it home from work, got back in the car 10 minutes later no start hooked up the scanner and it had a bad crank position sensor. So I would try hooking up a scanner.

Good point!! Only thing is, I dont think the 95's came with those sensors...

[Hamster Dance]

Just changed the oil and no start...
clogged cat maybe?

[02z28ls1]

Again you're jumping to conclusions without checking nothing out.Jam a screwdriver in the spark plug boot and holding the insulated end of the screwdriver see if you can get a spark against a ground nearby-it's got to be a good ground not something painted or insulated.You still haven't established that your injectors are receiving a signal-a "noid " light will do this quickly and effectively.If you have a distributor you don't have a crank sensor -that should be THE crank sensor-however I am not that familiar with the LT-1 as I am with the LS-1,maybe some body else will fill in the blanks here.You don't need to drive the thing for 30 minutes revving the hell out of it to clear the intake of unburnt fuel-2 minutes will suffice for that.How many miles does that engine have on it?If there is oil on the plugs I'm thinking you have a worn out engine-but let's not jump to conclusions again,it still should start,just with alot of oil smoke(blue).Another possibility is that the timing chain jumped a tooth if it's an older high mileage engine.In other words-you don't seem to know enough about this and it's impossible for us to check this stuff for you-to diagnose the problem.Is your engine an OBD2 or OBD1 computer-because the OBD1 will not throw codes all the time to help you out-96 and newer have OBD2 but there are older exceptions-it makes a big difference in establishing whether that "no codes" thing is important or not.In conclusion here-You may wind up towing it back somewhere if you cant diagnose this in a more logical and professional manner-I seriously doubt the cat. convertor is your problem