Does anyone know how to tell if the spark controller is working correctly on a 82? Drove the car tonight and she felt very lazy in performance compared to normal. Then it backfired under full throttle. It's always something....

 

Are you having the CHECK ENGINE light coming on????

DUB

 

No.

 

Perhaps use a timing light with the EST bypass still connected. I tried this on my 82 and the timing was wandering back and forth by about 3 degrees at idle, whereas with the EST bypass disconnected it was dead still. Then get someone to give it a rev and see if it advances. One way of checking?

Rich

 

That's a good idea, I'll check. I do have it timed at 10 deg. do you think that's too much? I do occasionally get that bad starter symptom after shutting off then starting back up after 10 minutes or so.

 

Is your on-board diagnostic system still functional? You indicated that the Check Engine (CE) light is not coming on when vehicle is running. But, does the CE light come on when you only turn the key to the ON position (prior to start position)? It should, if the computer is working at all. If it does not, then the CE lamp may be burned out and you would never know that the computer has detected a problem.

The kind of operating problems you described SHOULD have triggered a 'trouble code' condition that would activate the CE lamp. Investigate and report back.

 

I have my one set to 12 degrees base timing and it runs fine but I do use 95 octane, it's the lowest we have in the UK. Still I would think 10 should be ok, most crossfire people I have read use 8-10 base timing. The only issue I have since using 12 degrees is a higher idle.
If you check it cold you should see the timing advance as the engine warms up as well. Mine went from about 5 cold to 10-15 when warm and I had about 10 base timing when I did that.

 

Al, have you checked your plugs? I was having an issue with some popping and backfiring on acceleration soon after the rebuild. I pulled the plugs and they were pretty dark with carbon buildup. In your other thread you mentioned it takes a bit for your engine to warm up, perhaps you need to go a heat range higher with your plugs. I started out with colder plugs and after the issue started I went up a range and ran for a bit then rechecked. After two replacements I feel I've found the correct heat range and I'm not having any stumble or backfiring anymore. Do you know what heat range you are running now?

 

Mark I'm using the stock AC Delco heat range whatever that is. I'm going out in the garage now so I'll pull one and check.

 

Yes it is still working and the CE lap comes on when I start the car.

 

I did take the car out yesterday and drove her hard and she performed beautifully so I don't get it. It's like the car has a mind of his own. I did notice though a couple of times the tranny didn't shift down but I think I was at that point whether it will or not. Right around the 65-70 mph mark but when I shifted manually I had plenty of RPM left...

 

Pull more than one plug....just pulling one plug can give you false information.

Knowing that you are not having a CHECK ENGINE light coming on....because IF the timing circuit was unplugged...you would have a CHECK ENGINE light.

I know that I use my Kv tester(Kilo Volt) to check the value of spark at each plug wire AT THE PLUG. It has saved me more times than I can count on finding out that bad plug wires or a crappy spark plug due to oil fouling and age was causing it.

I would connect a scanner and make sure that your values fro the MAP, TPS are correct and that the coolant temp sensor is doing its job....along withe the Oxygen sensor getting hot enough to turn the computer on...so-to -speak and making the system go into CLOSED LOOP.

DUB

 

That's some good vital information, I'll check those. I did pull a few plugs and they all looked perfect. They had a whiteish-brown with no carbon. I double checked the timing and it was pretty advanced. It was about a 1/4" off the timing mark so I retimed it to 10 deg and brought the engine speed up to see that the timing mark was moving which it was. Now I don't know if this would make a difference but last time I set the timing I used #1 at the distributor and this time I used it off of #1 plug. I will say my idle came down nicely and while the EST was unplugged the CEL was on and cleared it with the battery disconnected.

I have a scanner that will read data so what should I suspect for those mentioned?

Thanks so much
AL

 

You have Edelbrock heads, right? They require a gasketed spark plug where our factory heads required a tapered seat type plug. Looking at the site shows they recommend Champion RC-12YC, which is what I started out with, but was way too cold for the application. What did your plugs look like when you pulled them? And Dub is right, don't just pull one, look at all of them.

Oh, I see you did pull a few, cool

 

Crap how did I ever miss that....Do you recall which plug you have? How can you tell if it's too cold? Will it be carbon'd up?

Yes I have the Edelbrock heads and just to be curious I checked my TPS and had .720V?? I reset it back to the .525 but I'm going to replace it cause every time I check it it seems to be off.

 

When I checked mine after having issues two of them were fouled pretty bad, # 8 and #3 were black, the rest looked okay, but were starting to carbon up. That was when I was running the Champions. I went to NGK at a heat range of 7, which was 3 colder than stock. They did better, but after about a month started the same behavior as the Champions, so I pulled them. There was nowhere near the amount of carbon buildup on #3 and #8 the second time, but all were uniformly darker than they should have been, so I figured I was still too cold. I went up to a heat range of four (recommended for a stock 350) and haven't had any issues. I'll pull the plugs again to inspect in a few more weeks. NGK's site has a great write up on heat ranges and how to tell if you need to go colder or hotter on your plugs. Gap the plugs at .045 just like you did for the original heads. If your plugs aren't loading up with carbon there is no need to switch heat ranges though. Check all the plugs anyway, and be sure you have 14mm 3/4" reach gasketed plugs installed and torqued to around 10 ft lbs. The plugs that were in the original iron heads were .460 reach tapered seat, so I don't think they'd even screw in at all, but I could be mistaken, I've never tried it.

Here is the write up link at NGK: http://www.ngksparkplugs.com/tech_su...2.asp?mode=nml

Plugs I'm currently using: http://www.summitracing.com/parts/ngk-5155/overview/

 

Thanks Mark.

 

Man I feel like a idiot!! I've been comparing the difference between tapered and flat gasket plugs. I wonder if that will make a difference. I'll buy a new set tomorrow. The correct ones that is...

 

Let us know how it works out

 

You should have a major improvement....due to the longer threaded portion of the plug actually gets in the combustion chamber and NOT causing a hot spot due to the shorter plug. Just did one a few weeks ago....taper plugs and they were wrong for the aluminum heads....and changed the heat range for street driving.

DUB