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Can you post a pic of your spark plugs? Do they all look the same? Could help figure out what’s happening. If one is different you may find your problem cylinder. The coloration can tell you a lot about combustion in the cylinder.
My dad and I have read the plugs a few times. They looked great to us maybe a little rich but good. Last time I pulled them about a month ago this is what they looked like. They all looked like this and because of that I stopped taking pictures. The oil on the threads was from spilling it all over the place while filling. (I tried to be all fancy and not use a funnel...) I think I was in the ball park on it running good, that was also before I pulled a little fuel out by lowering the fuel pressure. You know to get the blm from 110 back up to the 120s. Like I said it's only in that mid rpm band, sometimes it's like a brick wall rev limiter and won't go past 3000 and others it will slowly miss past it and after you're over 3500 it clears up and is fine. I haven't experienced it at low rpms <2000 except yesterday but I think that was more than likely because the thermac flaps were closed because it was still cold and it was rich because of it. After it got up to temp that went away and it only did it a little bit when it was cold anyway, kind of like how a car with a choke on runs when cold. Normally I let the car warm up before driving it that was a rare time I actually needed to be somewhere fast.
I’ll admit I’m not the best at reading plugs but you’re right from looking at those I’d say you’re running maybe a tiny bit rich, which would suggest spark or airflow issues. Have you checked to make sure your air filter isn’t clogged? I doubt that’s it but good to verify the basics at least, right?
It it was recommended to me to check that the distributor doesn’t have any play in it by removing the cap and trying to wiggle the rotor. If it wiggles it may do that at high rpm and cause weak spark. I believe you’ve already checked the cap, rotor, ignition coil, plugs and wires, right?
Yea I did a wiggle test. I pulled out the distributor a week ago to replace the pickup coil and shim out some end play. The magnet on the coil was cracked and I had thought I found my problem but no dice. I don't have any side to side movement I can see. And I'm really laying on it. Spark at the plugs is nice and blue. Like I said when I took that picture I was data logging the car running rich and it couldn't pull out any more fuel via blm so I lowered the fuel pressure to get it better. By doing that data logging showed everything being about where it should be. I may pull them this weekend to check again if I have the time.
do a test of the Throttle Position Sensor .and check all grounds .
Will do on the grounds. As for the tps, I have closed voltage set and I get a smooth voltage sweep as I move the pedal so it seems fine? I don't want to just throw parts at it. Up until this point everything I replaced was marginal and improved upon some problem to an extent...
Will do on the grounds. As for the tps, I have closed voltage set and I get a smooth voltage sweep as I move the pedal so it seems fine? I don't want to just throw parts at it. Up until this point everything I replaced was marginal and improved upon some problem to an extent...
So I just remembered a bit of information. I tested the knock module by placing a long screwdriver on the block and smacking it at idle. My dad said it pulled about 2 degrees stayed like that for a few seconds then advanced itself back to where it was. Is that the normal operation for the est?
Didn't have the chance to pull the egr yet but got right in and drove and behaved well. Air is also dry and about 55 degrees so it should be. Will test later especially if it starts acting up.
So it overall ran really well today. It messed up a little but I never had the chance to pull the egr line. I forget my tools to get at the throttle body so I didn't bother. I was getting on the parkway and stabbed the skinny pedal in third from 45 and counted to about 8. I looked down and was borderline triple digits... like really borderline. And it just wanted to keep pulling. I really wasn't expecting that. Anyway I noticed after running at 70 for a couple minutes the overdrive would kick out. Dash said 180 so I imagine the temp sensor was below 176 and thus disengaged it. After 20 or so seconds it would kick back in... So I think it's borderline too cold. I may swap to a 195 instead of a 180 degree thermostat. Forecast shows mostly rain tomorrow so I guess I'll be testing the egr next week. Anyway I'm speculating if the computer is seeing the car running colder than it is it could be adding extra fuel and it's fouling a little bit. I'm really liking how it pulls though. It's finally fun.
It seems to run better as you drive it. I pulled the cover and put vacuum on the egr solenoid. Couldn't pull any. Egr valve tests fine however. Seems like there may be a vacuum leak. Plugged it and the car seems better still. Hooked it back up and sprayed with starter fluid and no change. Vacuum gauge shows a leak on it though. Fingers crossed.
I picked up almost 2inches of vacuum at idle so now I'm sitting at about 20 and it hasn't even thought about trying it with that vacuum port plugged... I think I have it.
I picked up almost 2inches of vacuum at idle so now I'm sitting at about 20 and it hasn't even thought about trying it with that vacuum port plugged... I think I have it.
The only update I got was it seems to get better as you drive it. About 50/50 still according to him. I don't get it. Think it's time to start looking into the computer...
Hey man, solved my issue today, had a bad intake air temp sensor. Computer was getting bad data so it was giving the wrong amount of fuel to the engine. Have you checked yours? That’s a pretty easy fix.
Hey man, solved my issue today, had a bad intake air temp sensor. Computer was getting bad data so it was giving the wrong amount of fuel to the engine. Have you checked yours? That’s a pretty easy fix.
84s don't have an IAT sensor. They have a thermac air cleaner system. This keeps the air in a certain temp range.
10-29-2017, 11:27 PM
