I am having problems with my brothers car. The car is and 86 with the CCC. It's all stock other then the K&N air filter and Flowmaster exhaust. The problem I was having was the car was not running right and it had a serious loss of power. It would stall and sputter. I couldn't seem to get it to run right. So we sent the car to my friends Dad who knows a lot more about these. He said the carb needs to be rebuilt. So he rebuilt it. Got it back and it ran a lot better. To me it still seemed like a lack of power(hell I drive a supercharged minivan for a daily driver. There is a lot of cars that's going to feel slow to me.), but he seemed happy with it. He did say that the advance something or other needs to be replaced. But my brother was broke and the car seemed fine at the time. So life goes on and a few months later the car is getting bad again. This time it is hard to start, runs on for a good minute or two after you turn it off, bad gas mileage, lack of power. He keeps asking me about it. I have NO clue about these systems. If it was TPI, it would of been fixed by now. I have honestly no idea on what to do. Since the carb has been rebuilt(if people can trust him to restore a $150,000 dollar Shelby gt500, I think I can trust him with my carb). I was thinking on just replacing the whole ignition side. Change out the dizzy and the advance thingy and the ECU. And see what happens. Also going to change the cap and rotor, spark plugs and wires. Just did a O2 sensor not long ago along with the fuel filter. I am just running out of ideas. My brother is getting bummed about the car. He keeps asking me if it was my car, what would I do. I tell him go TPI. But he doesn't have money to do that. So if you guys have any ideas. Please let me know. Thanks. Adam :-)

 

It sounds like a timing issue - I'd check base timing and reset to factory specs. Plugs, wires, cap rotor. Make sure firing order is right.

You know you have to disconnect the EST wire to check base timing right?

You know how to get TDC compression stroke on #1 to check firing order?

Car have any SES codes? Grab a paperclip and check codes:
https://www.thirdgen.org/service-eng...ht-error-codes

 

Timing is what it sounded like. I adjusted it before. And yes I know about that one wire plug thingy for the timing. Firing order should be correct. I'll check again. It did have a check engine light on. But my dumb self diconected the battery because the stupid alarm kept going off every time an acorn would drop on it. I do have a proper obd1 scanner I can use. I use it for my tpi camaro. If there is any parameters I can look at let me know. Thanks again for the help.

 

The advance is built into the ECM. Check the code(s) being set (as evidenced by the SES light being on) - if you get anything at all, it probably isn't the ECM.

All of those things should be done before anything else.

The most common ignition problems are cap, rotor, wires, plugs, coil, and distributor module.

Check the trouble codes before you do ANYTHING! Why not listen when the car is trying to tell you there is something wrong?

 

The cap, rotor, plugs, wires, fuel filter, o2 sensor and carb rebuilt not even a year ago max. Was just going to replace some of that stuff again because it is cheap and easy. Peace of mind kind of stuff to rule out being bad. And as far as the codes. Last time I checked it said o2 sensor. Like I said it had a light on last night. But beening a dumbass I diconected the battery and cleared the codes by accident do to the alarm going off at the slightest bumb. I might try hooking it up and going for a drive and see what happens before I tear it apart.

 

Actually. I might not take it for a drive. Brakes are shot plus he has a collapsed brake hose or a sticking caliper. He treats his cars like crap. Feel like slaping him. Slightest thing on mine they get parked till fixed.

 

Any updates on this?

My car has some of the same problems: Horrible gas mileage (I estimate 11mpg MAX on a good day), dieseling, lack of power, also has spark knock..

Just wondering if you made any break-through's.

 

Start a new thread on your drivabilty issues ( with a little more detail ) and maybe some poeple here can help you out.

 

No break-trough's. But I did start it up today and did notice while I was scanning it. That some of the readings would work most of the time and or they would adjust real slow. Also the service engine soon light would light up dim and flicker while the scanner was hooked up. And after it died because it ran out of gas. I checked the codes. And they were both o2 codes. One for being faulty and the other for being too rich.

 

IMO these cars will read/burn rich unless really warmed up. And when in park/idle I'm not too worried if burning a little rich (trying to keep the car moving anyway, right?). My car will tend to through a code if it's 1/2 way warmed up -- I ignore the code and a minute later it clears itself after driving (just so the car isn't sitting idling). My wife's minivan is great at idling but not my old camaro engine.

 

My brother said his car dose exactly this. Other then the problems he has at the current time.

 

The carb may have been rebuilt properly, but has it been adjusted properly on-car? TPS, correct normal and high idle speed, idle air dwell, front mixture screws, and all that choke linkage? Is it going into closed loop?

Also if you have the smog pump system, try taking the belt off for a while. Sometimes the diverter freezes up and it'll dump air into your manifolds all the time (before your o2 sensor) confusing the sensor and throwing your mixture way off. Happened to me.

 

I'm going to probably say yes to this. I just dropped the car off and he did everything else. So he took it off and rebuilt it and put it back on and tuned it. Car was absolutely awesome when we got it back. Still had a lack of power to me. But I daily drive a 300hp minivan. So it probably was fine. But it just seemed to get worse after a few months till it was not driveable anymore. Hard to start, shakes at idle, loss of power, stalls when you try to do a very small brake stand and it runs on after you turn it off. And some times its so bad he can get to his third floor appartment before it will finally shut off.

I'll take a look at that smog pump. I'll take the belt off and see what that dose. I am also going to replace the o2 sensor sense it is still under warranty just for peace of mind and I know its good.

 

I admit it... overall an LG4 is not an exciting engine... just something to drive and tinker with, but you said there was a performance decrease... varnish? did car sit or get bad fuel along the way? seafoam ... can of carb cleaner ... new gas ... new air filter... cheap ideas that might work!

 

First off, what do you mean by 'advance something or other' and second, if you trust his skills why did you ignore his advice? If something needs to be replaced, then it needs to be replaced. Cost can sometimes be an issue, but you can't just not do it if it needs to be done.

You say the carb is adjusted properly, but don't tell us exactly what you did and how. Give us specifics.

What is the timing set at and what is the spec for your engine?

What do the plugs look like?

 

Car was a daily driver. Never sat. It has been through multiple tanks of gas since acting up. Things we have replaced recently. K&N air filter, fuel filter, spark plugs, spark plug wires x2, cap & rotor, water pump, radiator, belts, thermostat and had the carb rebuilt. The only other thing is the previous owner added flowmaster exhaust to it. Then some other stuff that wouldn't matter like a/c, shocks, etc...

On the bright side. I was looking through my factory 87 service manual to figure out my "gas tank has way to much positive pressure and is sending the $40 I just spent on gas srait on to the ground" problem. I stumbled accross the section for the LG4. I thought 86 was the last year. But I guess it was 87. So now I have a factory service manual that I can read and study. Already learned that the ecm refreshes every 1.25 second. That that explans why yesterday some of the values on the scanner were not making the change right when I did it. So I guess I am going to do some reading. Been there done that before making custom wiring harnesses. Me and the books spend at least a good week together. But by all means. If someone has an idea that can get this thing fixed faster, so I can get back to my car. Please let me know.

 

It was the ESC(electronic spark control) from what I could gather. Yes I trust his opion greatly! He is the only mechanic that touches my IROC other then me or my friends. But this is my brothers car. He has only so much money and so much broke on the car. If it was just this problem. I would buy the $70 part and call it a day. But since he needs engine, brake and suspension work done. Every dollar has to be streched. Hince why I am trying to make sure what I replace and buy fixes my problem. The other parts that I already replaced like plugs, wires, etc... where parts I had laying around that I never used or under warranty from the last time they got replaced.

Timing is set to zero and plugs were black from being on the rich side.

 

What did you do to tune the carb? What's the dwell? Is your Check Engine light on? If so what are your codes? What's your TPS voltage?

ESC is your knock sensor. I run an Olds and we didn't have them, but I know how they work. They retard your timing when they sense knocking. Could it not be possible it's detecting knocking all the time hence retarding your timing all the time? Be a good big brother and buy him a new knock sensor!

If your car's running rich, you need to find out why. These cars ran lean if anything.

 

Easiest and 1st, if you have not already done so, check the spark plugs. Make sure plugs wires are on the correct plugs. And check the rotor inside distributor cap, could be corroded. But if at absolute worst, it could have a dead cylinder. And couldn't always hurt to redo the timing. Especially if it was anything like mine, it had a loose intake manifold, so antifreeze was leaking into #5 cylinder causing it not to fire. Quick gasket change and was fixed!

 

I did not tune the carb. I don't have the slightest clue on how. Last time I tried messing with a carb, I lost $1000 on the resell of a Camaro because I could not get it to run right. Hence this post. I know TPI. Dwell? I am guessing that is for crab cars. If the scaner dose not show it. Then I have no clue. I don't have a dwell meter. Yes the SES light was on. Don't remember the ecat codes. But one was for faulty o2 sensor and the other was for o2 sensor to reading to high/rich. TPS voltige was around 1.43volts if I remember right.

Ya I know the ESC controls timing if it hears knock. That is what I was thinking it was doing. But there are no codes for it. I just want to make sure it's that before I go replacing parts all gun ho.

And yes I do want to find out out why the car is running rich. But since it is a carb. I have no clue what to look at.

And actually I am his little brother. Well younger brother. lol. I do enough for him already without having to spend my money I need on my cars on his car. There is just this thing in are family about all this. He is my only Brother and I love him. But, basically we do this for his kids. And we will just leave it at that.

Plugs where pulled and cleaned. Wires were checked and put in order. Cap and rotor were checked and in good shape. Once the rpms get up it dose great. but I did notice that when you floor it you get white smoke. I thought it might just be condensation. But it might be more to it. Might have to pressure check the system. It doesn't over heat at all sense the new water pump and radiator.

 

set the timing to 4 to 6 degrees BTDC, that will help wake up the engine and won't hurt at all

 

I agree about 4 to 6 btc timing (with wire unplugged). Mine sometimes "sneezed" through the carb when it was at 0. I noticed no power difference changing it though.

TPS should be at .48 volts with the car warmed up, choke fully open, and idle set at the correct 500 or 600. Measured through the bottom 2 of the three wires in that plug. It should slowly increase voltage to about 5volt at wot.

Somebody's gonna have to spend the thirty bucks for a dwell meter. If you drive a car with the quad, its like a timing light or multimeter, just one of those tools you cant go without. http://www.actron.com/product_detail.php?pid=16160 They sell it at advance auto (special order when I got mine) also I've seen it at sears.

I believe that if you unplug your knock sensor, the computer wont notice, and if you're getting false readings that should stop. Just listen for knock really closely. Theres also a way you can check the module. One of the pins puts out a constant 9v(?) until it detects knock. Then it cuts that signal, the ecm notices this, and retards the timing.

 

another cheap trick: every two to three weeks of running the car nicely to save gas 1) check the oil level, 2) buckle up and warm up the car, and 3) just have some fun by smashing the pedal to the metal a few times. This will result in a lot of carbon and garbage being blown out the back. And a reasonably big smile. Part of my routine -- honest!