Replacing fuel injectors, plugs and wires

[bingalls]

My 90 GS Custom recently stopped moving. While in Park I can floor the gas and get plenty of response, but once in drive absolutely no acceleration and RPM's will not go past 2100 . My mechanic linked it to a fuel injector problem which I have had before with this car.
This weekend I am going all out and replacing all the injectors plugs and wires . Just wondering if anyone has ever had this happen or hasdone this and knows any easy way to get to the three plugs on the backside of the engine. Any tips on the fuel injectors would also help

[01regalGS]

The easiest way to replace the rear plugs and wires is to: 1. remove the front engine mounts (dogbones). 2. leave car in park and push forward until the engine just touches the fan. 3. depress parking brake. 4. remove the bar connecting the struts.

Its still tight back there but at least you can get a socket on the plugs.

I question the diagnosis of plugs, wires and injectors. My Regal just had the same problem and it was the catalytic converter.

[bingalls]

Is there any way to diagnose if it is the cat. conv. without removing it?

[01regalGS]

When I took mine in they asked if it sounded like a vacuum cleaner when I tried to accelerate. You could also let it run for a while and see if your tailpipes get hot.

[bingalls]

They did get hot after my mechanic was punching on the gas to hear the engine. There was smoke pouring from the outsides of the exhaust pipe down near the cat.

Thanks for the reply.
I think i am going to start with the plug wires becase 2 of them snapped off in my hand when i tried pulling them off.

[BNaylor]

Originally Posted by bingalls

Is there any way to diagnose if it is the cat. conv. without removing it?

You can run a vacuum check by connecting a typical automotive vacuum gauge (0 - 30 Hg) to see if the CAT convertor is clogged. Just connect to any vacuum source off the intake manifold or throttle body.

Run the rpms up to around 2000 - 2500. The reading will intitially stabilize and then if it starts dropping off towards zero or to yellow and red areas marked on gauge, there is a high probability the CATs clogged or there is other exhaust restriction.

[bearcat5]

Remove the O2 from the exhaust; Put any kind of hollow adapter in place of O2. Attach a hose from the adapter to a pressure gauge. Start car and watch the pressure. You'll have to check the book to see what the back pressure should but from what I remember it shouldn’t be any more than 2lbs at any given RPM. If it is change the cat.

[BNaylor]

Originally Posted by bearcat5

Remove the O2 from the exhaust; Put any kind of hollow adapter in place of O2. Attach a hose from the adapter to a pressure gauge. Start car and watch the pressure. You'll have to check the book to see what the back pressure should but from what I remember it shouldn’t be any more than 2lbs at any given RPM. If it is change the cat.

Good suggestion. But here's some additional info for clarification:

The gauge needed for this method is a low pressure (0 - 5 psi) gauge.

After connecting test fixture, the engine should be warmed up to operating temperature and then rpms run up to 2000- 2500.

Note reading and if it reads greater than 1.25 psi, the CAT is clogged or the exhaust system backpressure is excessive.

BTW - This is in accordance with the GM service manual for the Buick Regal.

[bingalls]

Turns out it was the spark plugs and/or wires.

I replaced all 6 of each over the weekend, something I never want to do again unless i get paid. Now the car runs like new (almost).

If anyone needs to know how to get to the three reaer spark plugs I found a somewhat easy way to do it without using an engine hoist, just the original car jack.

Thanks for all the posts, I may need the tips in the future

[GTP Dad]

How about filling us in on how to reposition the engine using the original car jack!

[bingalls]

First off you will need 2 people to do it.

First support the engine just behind the alternator with th car jack to keep the engine from falling backward toward the firewall.

Next, remove the 2 front engine mounts from the engine block. Once the engine mounts make sure the car jack is ready by wedging it as far as you can behind a sturdy spot on the alternator. Find one of the engine hoist rungs on the side of the alternator, should be right in front. Using a pry bar or large socket wrench handle pull the engine forward while the second person guides the car jack down between the alternator and the firewall. Make sure the car jacks top side is facing the alternator while doing this. If you look behind the alt. you can see a squared off section of metal sticking out this is where you want the car jack to rest. It takes a bit of muscle to pull the engine forward by hand but once you get the car jack in you can then use it to "jack" the engine forward enough to remount the engine. If you look on the wishbone enine mounts you can see a second set of holes just under and behind the actual mounts, us eone of these for a safety to hold the engine forward once you have it far enough. You can then let off pressure from the jack once that is done just to be safe. Note that i have only done this once basically flying by the seat of my pants so as youre going you might find an easier way. Hope this helps.

[bearcat5]

That is what thoese holes are for. You can put the car in netrual and with a pry bar insert it into the eyelet on one of the mounts thats used to lift the eng. that the wishbone came off of. Pull the eng toward the front of the car and it will rotate quite easy. Using one of the bolts from the wishbones, you line up the bottom hole of the wishbone to the engin mount and insert the bolt. You now have more than enough roon to change the plugs and wires.

[Ernie1969]

ANyone know of a easy way to change the 6 injector on a 1995 pontiac grand prix with a 3100 engine?

[BNaylor]

Originally Posted by Ernie1969

ANyone know of a easy way to change the 6 injector on a 1995 pontiac grand prix with a 3100 engine?

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