1978 Pontiac Bonneville - Fix it! - 2008-04-12

It's the weekend. Time to begin work to get this thing smogged and registered. It has a bad misfire that is causing it to not fire on all 8. The most important thing to do is verify what is the source. If we have rings or head problems, that is expensive to fix. Ignition\timing\fuel delivery are relatively easy to work out. But first we need quality pictures!



Ow. The guy said someone was backing out of a driveway and plowed right into him. It busted the hood, fender, and headlight bucket assembly. Luckily it missed the bumper completely.



Side view of the car. Pretty straight minus that front end damage.



Back view of the car. All tail lights work, which is a bonus.



Interior. A little dirty and grimy, but the tiny crack in the dash is the only one in it. All the grey stuff is just dirt (probably concrete dust judging by the big stickers all over the car).



Back seat. Lots of trash and receipts in here. Not very loved by the previous owner. Dig the power windows.



Cushy interior. Saggy 80's GM headliner is mandatory for a vehicle this age. I like the courtesy lamps on the quarter panels (almost like a Lincoln\Cadillac, but not quite!)



Full gauges! Idiot lights are overrated.



Speedometer. Trip actually works like it should!



Non-working GM clock is standard issue as well.



Audiovox AM\FM stereo 8 track with CB. The glove box had the original owner for the CB radio and his CB license from 1979 in it. All of the manuals and paperwork for the CB radio are in the glovebox too, including the entire schematic for it!



The Pontiac 400.



Grimy engine a bit. People always paint the valve covers to look pretty and leave the rest of the motor filthy. No idea why. The neon green looms are special...

So it is compression test time. Easier said than done, the #2, 4, & 8 plugs were nearly impossible to get out. The plugs look beautiful though.

Driver's side bank was done first:

#1: 145
#3: 145
#5: 120
#7: 135
Not bad. On to the passenger side:

#2: 160
#4: 152
#6: 160
#8: 130
Wow. And here I have always been told that low compression engines can't even get out of the driveway with their piss-poor compression ratios. My 455 had worse readings than that. So only cylinder #5 is low, but not low enough to even warrant a problem. Very good, not a problem with the rings or heads. Must be something else then.



Well this isn't a good sign. Lots of carbon and gunk on the rotor is a sign of breakdown all over the place. The towers were arcing everywhere when Steve and I pulled them with the engine running. Some of the plugs were not even snapping in place. Several wires are held together with DUCT TAPE. Somebody paid a shop good money for this work.



Cap button is junk. The coil's resistor pad is also covered with a ton of grease that has turned to sludge.



I pulled the weights off as they were so sloppy they were sticking together and apart. The springs were good, but not the weights. "053" is the number. No idea if this is original or not.



Instaled new weights without slop. They return as they should and don't float around on the studs.

So we need a new cap, rotor, and plug wires. No biggie, right? Wrong. Cap and rotor are no biggie as Chevy uses them, but the plug wires are made of unobtanium for 3-4 business days by everyone for some reason. Kragen says "yeah we have them" and I go over there only to be told "We don't have that" nonchalantly by the guy behind the counter. Dammit. I hate driving over to be told "NOT!" I drive over to E&M Auto Parts in El Cajon who have EVERYTHING. Not surprisingly, they did. $75 worth of parts later, I am set to go.



New distributor cap and rotor assembled. This car has a brown lead plugged into the tach lead for some reason. Not sure if you could get a tach in this car or if it is somehow for the cruise control (that doesn't work). Two plugs were gapped at 0.045 and the rest were gapped at 0.056(!). We gapped them all at 0.050, which is lower than the 1978 manuals say, but higher than 0.045 which I don't think is right for an HEI of this vintage (really, who knows).



All put back together and ready to run. I gained 50HP with the yellow plug wires. I could have gotten black, but they were 7mm wires and I wanted the 8mm with the high quality boots on them so I had to live with the yellow. I'll paint them black if I get annoyed enough. The engine runs considerably better than before, but still runs rough. Vacuum leaks must be ruled out!



EVERY vacuum line on this car is crunchy. Most don't even go anywhere and are hidden. This obviously won't do. New vacuum lines for everything!



Now that EVERY vacuum line has been replaced, we're ready to fire it up and see how it behaves. The sheer amount of laughs this routing gave was amazing. The cannister vacuum line was tucked under the compressor and electrical taped together. The head thermal vacuum break was completely left off and the lines were hidden under the distributor. The EFE line was missing completely. The main vacuum line to the EGR was plugged with a screw and disintegrated into 4 pieces upon being touched. How the car ran so well with all of this is beyond belief. It fired right up and idled considerably smoother than before. Absolutely no stench comes from the tail pipe anymore unless you stick your nose right in it. It used to melt paint off of cars getting too close, now it barely has anything coming out. Might just be enough to pass smog unless the misfiring went on so long that the cat is junk. I can't believe that all this needed to clean up and smooth out was a new cap, rotor, and plug wires. Or that someone actually paid someone else for the mediocre crapjob that was done.

No success story is complete without video of running the engine here.



No new car is complete without the parts list! There is a ton of stuff in the trunk. The original front driver's side tire was ruined in a blowout about 6-7 months ago. It's a shame too.



If I wore a size 8.5, I'd be set for heels. There's like 10 pairs in this box. There's also various coffee cups, a 5W-30 oil bottle (not on this car I hope), a 10W-40 oil bottle, the original owner's manual, a book on horses, a bridle, Christmas cards addressed to the previous owner, overdue bills addressed to the previous owner's 2-3 relatives, self-storage late fees to the previous owner, and a brand new 50ft garden hose still in the bag.



Oh yeah, clear heels! Never thought I'd pull a set out of a car, but here we are!



Gumby went for a ride in the trunk of this car. Steve claimed the cup for his "strange finds" collection along with a Burger King plush whale kids toy from some promotion a while back.



A 2.41 open rear end with tag still on it... Gear oil has probably never been changed either...



A factory 11" 3" deep drum. The brakes on this car suck, but the rotors and pads are great.



Except the back drums and shoes are wasted. The driver's side is VERY thin and has two rivet ridges worn into it. Ah well. Only $30 from AZ and pads are $20. The passenger side is ALMOST ruined, but luckily it has some life left.



Ready to drive home (almost).

A very productive day. I managed to get the car running without any issues being exposed. Found out why the brakes suck too. Steve is going to run the car to his favorite smog check station and see if we can't get this thing smogged (and thus registered) next week!

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Last updated April 12th, 2008