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Discussion Starter · #1 ·
OK guys.. I have an issue.

I think I have a timing issue on the ol' silver bullet. I have a 305 in it.

My sticker says timing should be set at 0 degrees BTDC. Any advice on where I should have it for good performance?

Right now I'm getting 17-19 MPG but it just absolutely runs like ass. When I pull out of my driveway in the AM onto the main road and hit the gas, it just wants to puke out on me. Once I'm up to 60-65 mph and punch it, she moves. I'm just terrified of it dying out and having a Kenworth park itself in my trunk.

I've already done spark plugs, wires and distributor. I've changed the air and fuel filters.

I have not checked actual timing yet, I'm looking to buy a decent timing light tonight or tomorrow.

So, what is a good range to shoot for? I really don't want to give up any fuel efficiency, I just want it to run better! Thanks in advance guys...
 

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0 degrees? Thats retarded :biggrin: get it? Seriously though, it may recommend that, but I would advance it. That is the 9.5:1 compression motor right? I'd try 6 or so and see how it does. Basically, if you aren't getting spark knock or overheating, you can go as high as you want. Play around with it, use whatever grade of gas you are comfortable buying consistently. Higher octane will give you more room to play with.
 

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Discussion Starter · #3 ·
0 degrees? Thats retarded :biggrin: get it? Seriously though, it may recommend that, but I would advance it. That is the 9.5:1 compression motor right? I'd try 6 or so and see how it does. Basically, if you aren't getting spark knock or overheating, you can go as high as you want. Play around with it, use whatever grade of gas you are comfortable buying consistently. Higher octane will give you more room to play with.
Yep, that's what the sticker says. Sounds retarded indeed! No overheating or spark knock unless I really floor it at low speeds. I generally buy midgrade (gas discounts usually put it a few cents above regular) but I have the budget to go higher if I need to.

Thanks man! :icon_thumleft:
 

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I run my 305 '92 Caprices at O degrees TDC and they run real well, lots of pep.

I would get them running at that first before I'd start tweaking, because if they don't run right there then there's some other problem.

On mine, you need to disconnect an electrical connector when you do the timing.

I'd check the strength of the spark visibly to see if it's strong. It should be able to arc at least two inches with a big spark.
And make sure your distributer cap and rotor aren't all corroded, sounds like you did that.

In the old days it was pretty standard to set cars at 10 degrees, but with computer controlled cars I tend to go by the book.

Also, make sure your EGR valve isn't making a massive vacuum leak. My Caprice had a vacuum leak in the back of the heater controls where a hose attached. I could hear it. It's a really bad design they went to where the heater controls are vacuum operated. Who thought of that should be fired.

But I can smoke 90% of the big exhaust Accords out there, and almost in total silence, with it at zero degrees.
 

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Discussion Starter · #5 ·
I run my 305 '92 Caprices at O degrees TDC and they run real well, lots of pep.

I would get them running at that first before I'd start tweaking, because if they don't run right there then there's some other problem.

On mine, you need to disconnect an electrical connector when you do the timing.

I'd check the strength of the spark visibly to see if it's strong. It should be able to arc at least two inches with a big spark.
And make sure your distributer cap and rotor aren't all corroded, sounds like you did that.

In the old days it was pretty standard to set cars at 10 degrees, but with computer controlled cars I tend to go by the book.

Also, make sure your EGR valve isn't making a massive vacuum leak. My Caprice had a vacuum leak in the back of the heater controls where a hose attached. I could hear it. It's a really bad design they went to where the heater controls are vacuum operated. Who thought of that should be fired.

But I can smoke 90% of the big exhaust Accords out there, and almost in total silence, with it at zero degrees.
OK good. I picked up a spark plug/wire tester last night. I'll putts around with that tonight when I get home. I looked at the EGR and it seems a little sticky so I decided to throw a can of carb cleaner in it and my throttle body. That actually helped the performance a great deal, but it still sputters just a little bit pulling onto the street I live on (a rural highway).

I've done this before and it helps for maybe a week or so and then goes right back to where it was. Maybe this time it will be different.

Yeah, I replaced the cap and rotor and I finally found that elusive hold down bolt for the distributor. Still not sure how I'm gonna get a wrench or a socket down there to loosen it up to adjust timing but I'll figure it out. I'll check the EGR valve again too for leaks. The base of it is pretty rusty.

Thanks Dintymoore. Any more feedback anyone else?
 

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To get to the timing bolt I use a socket with a universal joint attached to it. I wrap masking tape around the universal joint so it doesn't flop around. Then I put a short extension on it (6-8" not sure) and then I use, instead of a ratchet, one of those fixed handles if you know what I mean, so you can tighten then loosen without hassle. The distributer wrenches I have don't reach.

Everytime I'm where you're at and I think it's the timing it never is... hate to say...

Another one: watch your engine in total darkness and sometimes you can see shorts! It's a light show folks.

There was a factory memo on these cars about the some spark plug wires (6 or 8) possibly being too close to one of the sensors on the passenger side.

It's almost always something stupid simple like a spark plug wire that looks good but actually is just barely connected inside on the spark plug end, or a new part that's defective.

good luck and think of how much you could get ripped off if you were paying someone to do this!
 

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Discussion Starter · #7 ·
To get to the timing bolt I use a socket with a universal joint attached to it. I wrap masking tape around the universal joint so it doesn't flop around. Then I put a short extension on it (6-8" not sure) and then I use, instead of a ratchet, one of those fixed handles if you know what I mean, so you can tighten then loosen without hassle. The distributer wrenches I have don't reach.

Everytime I'm where you're at and I think it's the timing it never is... hate to say...

Another one: watch your engine in total darkness and sometimes you can see shorts! It's a light show folks.

There was a factory memo on these cars about the some spark plug wires (6 or 8) possibly being too close to one of the sensors on the passenger side.

It's almost always something stupid simple like a spark plug wire that looks good but actually is just barely connected inside on the spark plug end, or a new part that's defective.

good luck and think of how much you could get ripped off if you were paying someone to do this!
Thanks again fo rthe input. The main reason I suspect timing is that I had the head gaskets go on me about 9 mos ago. When I got it back is when it started running like ass. I figure the guy must have gotten the distributor back in 1 tooth off or something. Plus a few other guys I know IRL have told me to look at timing. But I'll track it down eventually. Thanks!
 

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For sure if you had the heads done you should check the timing, and if it's like my '92 make sure you unplug that connector when you do it.

Another one is to look in the throttle body with the air cleaner off and visually see that the fuel spray looks good.

The reason I say that is that I had to do my fuel pump recently and in the weeks before that I'd noticed that the car was sucked out and coughed a bit.
 

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Discussion Starter · #9 ·
For sure if you had the heads done you should check the timing, and if it's like my '92 make sure you unplug that connector when you do it.

Another one is to look in the throttle body with the air cleaner off and visually see that the fuel spray looks good.

The reason I say that is that I had to do my fuel pump recently and in the weeks before that I'd noticed that the car was sucked out and coughed a bit.
Do you mean the connector on the distributor or the one on the ignition coil?

I took the air cleaner off entirely and sprayed it down with carb cleaner. For some reason I get a ton of sticky varnish residue after just a few days/weeks. Very odd.

Anyway, the fuel spray looked uniform as far as I could tell. Now the engine likes to act and speed up just a little and the fuel spray stays consistent so I don't think that's the problem. I've checked for leaky vacuum lines (though I haven't checked the EGR valve yet. And I probably should tighten down the intake manifold and the throttle body, though I have sprayed the area down with soapy water and saw nothing being sucked in or anything.

And I have no CEL codes stored either. Nothing since my knock sensor went out over the winter. That was a pain in the ass in itself!

I'll probably have to take it to my friendly neighborhood mechanic for some more avanced troubleshooting that I don't know how to do. Ugh!
 

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The one at the distributor, always disconnect the advance when checking timing. As for checking for vacuum leaks, I wouldn't go with soapy water, visual tests don't work so well for vacuum. Use carb cleaner or some other aerosol spray, spray around all vacuum fitting and hoses and listen for significant RPM changes, increase if you are spraying something highly flammable, decrease if not. And also, if it's been since having work done, check anything and everything that he touched. Check your firing order, make sure vacuum routing is right, no connecters unplugged, that kind of stuff. Start with the easy stuff.
 

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Discussion Starter · #11 ·
The one at the distributor, always disconnect the advance when checking timing. As for checking for vacuum leaks, I wouldn't go with soapy water, visual tests don't work so well for vacuum. Use carb cleaner or some other aerosol spray, spray around all vacuum fitting and hoses and listen for significant RPM changes, increase if you are spraying something highly flammable, decrease if not. And also, if it's been since having work done, check anything and everything that he touched. Check your firing order, make sure vacuum routing is right, no connecters unplugged, that kind of stuff. Start with the easy stuff.
Well, as long as this frickin' rain stops soon, I'll be working on her tonight. Otherwise I'm looking at tomorrow. (Yeah, no garage!) :frown:

Thanks for the input guys. I appreciate it!
 

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Do you mean the connector on the distributor or the one on the ignition coil?
On my '92, you need to disconnect this one:

then use your timing light and adjust the distributer if needed, then reconnect the connector.
That connector is the electronic advance, and I don't think most people will be able to get it better than the folks at GM did. It's pretty good.

please keep all rust comments to yourself

BTW, it sounds like you're getting pretty bad gas mileage, ok for a 60's Chevy with points, carb and slipping torque convertor but a '91 should be able to get a lot better. I think factory was 26 highway, and I don't think that's b.s., they can get radical gas mileage for two ton vehicles.
I think the the 1st PT Cruiser was only 2 mpg better on the highway and it was 4 cyl and weighed at least 1/2 ton less. Go figure.

(I'm gonna wild guess your car has 2 spark plug wires swapped.)
 

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On my '92, you need to disconnect this one:

then use your timing light and adjust the distributer if needed, then reconnect the connector.
That connector is the electronic advance, and I don't think most people will be able to get it better than the folks at GM did. It's pretty good.

please keep all rust comments to yourself

BTW, it sounds like you're getting pretty bad gas mileage, ok for a 60's Chevy with points, carb and slipping torque convertor but a '91 should be able to get a lot better. I think factory was 26 highway, and I don't think that's b.s., they can get radical gas mileage for two ton vehicles.
I think the the 1st PT Cruiser was only 2 mpg better on the highway and it was 4 cyl and weighed at least 1/2 ton less. Go figure.

(I'm gonna wild guess your car has 2 spark plug wires swapped.)

Hey, whats up with the rust? :biggrin:
 

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on your valve covers I think he means...
 

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god im so glad i live in colorado beautiful rust free state!!!! but my cars from AZ another hott rust free state .......:biggrin::eek:
 

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Discussion Starter · #18 ·
Well I still haven't had time to eff with the timing yet. I've done some lookign and haven't found a vacuum leak either. Hopefully this weekend! We have 2 nice days and it's gonna rain on Monday.

I finally got my hands on a decent Snap-On timing light, can't wait to play with it! :biggrin:
 

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There's a slot behind the water pump you can point the gun down. You can spray some carb or brake cleaner down there to clean it up. I usually get the timing mark to be visible from the underneath for access and put some whiteout on it and then wipe it so it's a nice line.
Up top I put some whiteout on the end of a chopstick and gently paint the timing tag to make it more visible. I've had whiteout last for years on engines and engine paint just fries off, go figure.

For whatever reason, as the years I'm familiar with went by (since '68) pretty much everything on these cars got more awkward.

On my '68 Impala you could reach the distributer hold down bolt with any regular wrench, and the distributer cap was held down with clips. The fuel filter was on the front of the carb... no glued-on mirror... I feel sick.
 

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Discussion Starter · #20 ·
Bump-o-rama & update.

I had time last weekend to play with this but I can't seem to locate this harness to disconnect the electronic advance to check timing.

I wonder if the dipshit that did my head gaskets maybe didn't reconnect this up? I also wonder where it went! I know my car has it, I remember seeing the connector. The only thing I have now in that location is a single wire connector that simply pulls apart and has no latching of any kind.

Where can I start to trace wires and figure out where this connector is?

Thanks guys!
 
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