1995 Pontiac Bonneville project

Hey guys I thought i would share my first car and what i am doing to get it fixed up.i got a 1995 Pontiac Bonneville with 175,000 miles for $350 from an older lady. so i thought why not, ill fix what needs to be fixed and not worry to much about cosmetic stuff. the car has been sitting for 1 year before i bought it last month so it had a rough idle and didn’t like to accelerate to much and it got worse to where i could barley pull away from a stop. so i changed the motor oil, oil filter, trans oil and filter, air filter, and 5 of the 6 spark plugs ( i was unable to get the rubber boot off of one of the spark plugs at the time of changing them, so ill get to that one when i have better access to the spark plug). After that it got a lot better but could still use some work. then i cleaned the mass air flow sensor, idle air control valve, and the throttle body. it then got better throttle response and has better accelerate too. man the spark plugs and throttle body where so bad, i think the plugs may be original. i have the parts to replace the break pads, shoes, rotors, drums and fluid too. ill update as i do more to the car.

Good luck. Check coolant, hoses, thermostat and serpentine belt too as first things.

Suspect you are correct about the spark plugs being original. Change fuel filter too.

oh yeah i forgot that i change the belt and fuel filter too. it also has a coolant leek some where around or on the water pump, its not real bad but i need to get that done. she doesn’t over heat or anything.

did you replace the spark plug wires? the 3.8 has a plastic coolant elbow in the tensioner housing. they always crack/leak. i dont see many 95 vintage GM sedans in mn. too much rust. i had a bunch of grand prixs over the yrs. mine and the kids. ok cars. did you open the throttlebore and clean the carbon out of the throat area? on both sides of the butterfly?

I did not replace the wires as they looked fairly new. I replaced the whole belt tensioner unit and got an aluminum coolant elbow I stead of plastic. I took the throttle body off and cleans every inch I could. That after pic was in the middle of me cleaning it.

I would recommend changing them anyway. They may look new, but looks can be deceiving. It’d be a shame to do all that good work and skip something as affordable as wires.

Please use the correct spelling “brake” pads, or you’ll drive us all insane.


It has become so common lately that I just ignore and go on however “break petal” will still set me off.

Sorry, typed that on phone and was multitasking.

I am not known for my spelling.

When I bought the car it could not be started with the key. it would run but u had to start it with a screw driver by climbing under the car, so I put in a push button that lets me start it from inside the car.

Good for you OP, you bought your first car. Seems like you are doing all the right stuff. $350, what a bargain! An entire (sort-of) running car for $350, think of all the technology you are getting for that price. One tip, if pushing that button cranks the engine, suggest to install an arm/disarm lighted rocker switch in that circuit too. So you don’t accidentally push on that button when the engine is already running. I have a similar “start” push- button I installed on my Corolla, but I decided I wanted to have the arm/disarm rocker switch too for the same reason. The push button won’t crank the engine unless the circuit is armed by the rocker switch.

That car is a nice looker too. A little cleaning/polishing/waxing work on the exterior finish will do wonders. IMO, that era, early 90’s, had a lot of nice looking cars. And just the right amount of tech, electronic computer controlled fuel injection, an airbag or two probably, but less of the electronic gizmos that add a lot of complexity but don’t provide much bang for the buck.

If your car has a conventional distributor (rather than coil-on-plug tech) if it hasn’t already been done, suggest to replace all the high voltage wires, the distributor cap, and the distributor rotor. And test the thermostat in a pot of water on the stove to make sure it is working correctly and opens at the right temperature. That’s a good time to replace the coolant too. I’d probably replace he PCV valve as part of the initial fix-up, they’re cheap as dirt and simple to replace. Don’t defer too long on replacing the remaining spark plug. Did you measure the spark plug gap on the plugs that came out? They look really wide, and running the engine like that can overheat & damage the coil. There’s no rule that says you can’t remove stuff that’s in the way first before replacing that last plug. With car repairs, from my vantage as a person w/ limited diy’er mechanic skills anyway, it’s usually faster to a completed job to remove the stuff that’s in the way first. Best of luck.

@George_San_Jose1 the car does not have a conventional distributor. the car is not over heating so i am not to worried about the thermostat yet , but i will replace it. the old plugs gaps are .070 and the new ones are .060.

Well, one of us anyway. :grin:

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More than one, A cardboard sign in the back window saying “car in toe” drives me nuts too and I have seen that at least 3 times.

Too of us to.


@George_San_Jose1 [quote=“George_San_Jose1, post:13, topic:108683”]
And test the thermostat in a pot of water on the stove to make sure it is working correctly and opens at the right temperature.

In heavens name why the test ? If you are going as far as taking it out just replace the damn thing.


car in toe? i get the concept. towing a car. but you have seen more than 1 cardboard signs in the windows of the car being towed? i have never seen a car being towed with a warning sign attached. maybe i should get out more!shopping


George advised: And test the thermostat in a pot of water on the stove to make sure it is working correctly and opens at the right temperature.

That works, but then the new one should be tested the same way before installing it.

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