Hey! I'm having a little trouble, maybe you guys can help me out. My car has recently been running pretty crappy. It runs good all the way to 75% throttle but at WOT it sputters and hesitates for a few seconds and then takes off. I checked the timing and it seems all ****ed up. The mark is way off the scale telling me that the timing is extremely retarded but if I bring it back up, the car putters and won't even start or stay running. The more I retard the timing, the better it runs. Plus, the car shoots moisture (maybe gas) out of the exhaust and slight white smoke when cool. It smells like it's running very rich but my A/F gauge tells me that it is running more towards lean. I thought I knew what I was doing, but then again, I'm really young and you live and you learn I guess, so if this is a stupid problem on my behalf, try to go easy on me. Thanks for the help!

 

You are checking the timing with the EST bypass wire disconnected, right?

 

I'm sorry, I'm an idiot. What's the ETS wire? I need to disconnect that to get a correct reading? I've never heard of that before.

 

First off its EST not ETS. You'll find this plug near the blower motor on the pass side of he firewall. I believe it is a tan wire. This is how the ecm advances/retards timing, much like vac advance on a non CC dist. You have to have this unplugged to set initial timing, because if you don't the computer will be advancing/retarding the timing as you try to set it, so it will not be true initial timing. Good luck.

 

Yeah, I know, I typed that wrong by accident. My brother was just telling me about that tonight when I spoke with him about it. He's gonna help me with it in the morning and I'll post the outcome. Thanks for the help. I'll let you know if it worked.

 

A-N,

The white "smoke" is probably latent moisture in the exhaust system that normally heats and evaporates as the engine (and exhaust)is warming up, and exhuast gas flow drives it out as vapor. I've accused that of being completely normal.

As well-trained as your nose might be, the A/F meter is probably better calibrated. I used to be able to tune "by nose" a little better, but that was in the day of carburetors and no cat converters. My nose has apparently long since lost its calibration, unless there is an extreme problem.

The EST system needs to be bypassed to set the base timing. thge connector is along the firewall, just like ssbowtie mentioned:



Remember that the engine rotates clockwise as viewed from the front, so that any timing indication toward the passenger (right) side is advanced timing, and anything toward the left side is retarded timing. This is basically the same, even in the U.K. and "down-under", except that the driver's position is reversed.

 

Okay, I disconnected the EST bypass and checked the timing. Still looks the same. Is there any tricks to get it to read the initial timing that I'm overlooking? I tried unplugging it, then starting the car, and tried unplugging it while it was running. Also, the mark looks to be unstable. Like it keeps changing possitions or stuttering. Is that normal? The car seems strong until I floor it. Then it gives off muffled pops but not like a backfire and the car hesitates. I must be an idiot or something but I am stumped.

 

Could be a lot of things. First, check your spark plug wires, and spark plugs. If your wires get old, the spark can jump between wires or other metal parts of your car. Could be a fuel issue too. Maybe a weak pump or a clogged filter. Good luck! Matt

 

I was thinking that it might be a fuel filter. I changed the plugs this morning and the wires are fairly new but checked them to be sure. I was playing with the timing though and it seems that the problem just got a little worse which is why I think it's the timing. I'm just having trouble finding the initial timing.

 

You may want to remove the #1 plug and setup TDC again. Make sure your distributer isn't off a tooth or that your timing just isn't so far out that it is screwing it up. My car was doing the same thing and I found that the timing was about 45 degrees out.

 

How do I do that? I heard that that's a pain in the ***.

 

It's not bad. Here is how I did it. It may not be the recommended way to do it but it works. Pull the plug, turn the crank manually until the #1 piston is all the way up. I put a screwdriver into the #1 plug hole to determine when the piston is all the way up. Make sure that the rotor is pointing toward the #1 plug on the distributor cap.

 

Do I take the cap off to check the rotor? And what am I feeling for when I stick the screwdriver in the plug hole? If I do this, my timing should be what when I check it with the gun and unplug the est? Thanks for the help, I really appreciate it!

 

Pull the cap but look at were the #1 plug wire is at. That is were the rotor should be pointing. When you put the screwdriver into the hole you are feeling for the piston. It should come up and hit the screwdriver. Be careful not to get the screwdriver stuck. If you do just turn the crank back the other way and pull the screwdriver out a little. Feel for when the piston is all the way up. At that point put the cap back on but make sure the rotor is pointing toward the #1 plug.

 

Make sure the rotor is pointing at the #1 point on the cap or at the spark plug itself? And the timing will be correct for me to set it if that was the problem? Sorry for being so annoying but I just don't wanna mess it up.

 

It should point at the #1 point on the cap.

 

It could very well be a fuel problem, does your car only hesitate like that at full or close to full throttle?, Your pump is probaly old and can not give the engine enough fuel fast enough, and your filter probaly is colgged, have you ever replaced any of this ? OH YEAH your timing is probaly not helping but this could make the problem a lot better.

 

Yeah, it hesitates at full throttle only and a little almost at wot. I was thinking that too, untill I saw that my timing was way off.

 

I'm confused. WOT is the same as full throttle.

Setting the timing is easy. Pull the #1 to TDC. I do it by turning the motor by hand until the 0* mark on the balacer is lined up with the center of the timing indicator that is on the timing cover. Make sure you're on the compression stroke of the cycle, or else you will set the timing off by 180*. Then notice on the distributor cap and see which post is the #1 cylinder. Mark with a permanent marker on the distributor housing where the #1 post is when the cap is on. This makes it much easier to get it right. Now check the distributor with the cap off. If the rotor is facing the mark that you made on the distributor housing, then your timing is set. If it's off, you need to re-install the distributor so the rotor is facing the mark. HTH.

Tony

 

I meant it stutters at wot and a little almost at wot which means it stutters slightly just before I reach full throttle and alot at full throttle. I guess I should have worded it better. I'm heading into the garage right now to try this. We'll se what happens.

 

I tried to fing tdc but I couldn't turn the crank with my hands. Maybe I'm a ***** or something but it seemed pretty hard to turn. I'm just gonna drop it off at the mechanic tomorrow before I screw it up anymore. Thanks for the help, though.

 

Put the car in Neutral. You should be able to turn it then.

 

Yeah, tried that. Still couldn't turn it.

 

I hate to tell you to do this but if you aren't able to turn it, you may have to take it to a shop and have them set your timing up for you. I hate for you to take it to a shop if that isn't the problem. Are you using a 1/2" socket on the crank pulley bolt or are you just trying turn it with your hands?

 

Get a 5/8" socket on a breaker bar and turn it with that with the car in neutral. It doesn't matter if it's an automatic transmission. Take the belt off too. That will make it easier to turn. If you still can't turn it or if it's hard, pull out the spark plugs. That way you wont be fighting the compression of the motor. Don't worry, you're not a ***** just if you can't turn the balancer by hand. Show me someone that can and I'll give them a dollar.

 

Yeah, I WAS trying it with my hands. I was thinking "damn, all these years at the gym and I'm the only person that can't turn this damn thing". I'm calling my mechanic in the morning. If he can't get me in tomorrow I'll try again after work. I'm thinking it might just be a fuel filter anyway but I already messed with the timg so much that it would be good to have it reset.

 

Sorry man, I should have made that a little clearer in my earlier post.

 

Heh, don't worry about it, buddy! I should've thought of that anyway.

 

Well, the timing is perfect, the fuel filter is new and all that good stuff. But the car still runs bad at WOT only. I'll try changing the wires now.

 

Is your fuel pump good?

 

Yup, had it tested.

 

It could be a timing advance issue. The PE timing tables could be messed up and be retarding the timing too much during power enrichment or advancing it too much causing alot of knock and the knock sensor is retarding the timing. Do you have the stock PROM ( chip ) in the car or has it been replaced by an aftermarket or custom one? It may be a good idea if you have acces to a PROM burner and software to zero out the PE timing tables and see if that helps at all. May not be the problem, but my car is doing the same thing and that's what some guys are telling me to do. Just thought I'd throw another idea at you since you haven't gotten it straightened out yet. HTH.

Tony

 

That sound like a good idea. Where could I get the software and is that a hard thing to do? I'm gonna try new plug wires next. That's what my mechanic recomended. My mech bill from yesterday was a little high and I'm broke so I have to wait till friday to get some new wires. Hope that works though. I was planning on getting the PROM burning software, though. I have a stock computer but it has a JET stage 2 chip.

 

Oh, and my car is running rich all the time, even at idle, although my A/F gauge says otherwise. How can I switch the A/F ratio?

 

You can adjust the a/f ratio with the PROM burning equipment. The software is free, but you need to get a programmer, $150, and a ZIF socket and adapter along with some chips. The cheapest way to go is to get the package deal from Craig Moates. It's $60 and all you need except for the programmer itself. Once you get the stuff, it takes a while to learn how to alter all of the parameters. Read Traxion's tech article and browse the DIY PROM board . I would personally sell the JET chip, you'll sell it for more than the benefits from it are worth. It just adds a little timing at the top of the tables. You'll do much better yourself when you start burning your own chips. Trust me

Any other questions, just ask.

 

Cool. I'm gonna see If I can hook myself up with a laptop first. Maybe I can just borrow my brother's. I'm strapped for cash right now, though. Trying to troubleshoot this problem has been killer on my pockets. Maybe I'll pick that stuff up this weekend after pay day.

 

A little more info, please.

What is the spark plug gap?

Heat range?

What is the condition of the distributor cap and rotor?

What is the fuel pressure?

Do you still have the stock PROM? Have you tried to install it for diagnosis?

 

The car runs at about 200 degrees, the plug gap is 60, the cap and rotor are new and the PROM is stock except for a chip. The car is also free of any trouble codes.

 

oh, and the fuel pressure is 40 psi.

 

I think he meant the heat range of the spark plugs. What kind are they?

 

They are Split Fire plugs. I know that they aren't very good but I changed them in a hurry to see if that would fix the problem and they were the only ones I could get my hands on on the 4th of July.

 

Man, I think your total post count is from this thrad only!

Anyway, have you verified that the fuel pressure isn't dropping at all at WOT? If that's the case then the motor could be starving for fuel.

 

Yeah, I've been counting on this thread to help me out a little too much! My fuel pressure is fine throughout the whole throttle range. I also drove around with a Snap-On diognostics tool attached to check everything. The only thing wrong it told me was that the car is constantly running rich, which I guess is the opposite of the engine starving for fuel.

 

Are the plugs fouled out at all? Pull the spark plugs out and look at the electrodes. A fouled out plug could definitely cause misfiring. If the car is running way rich, it will cause the plug to foul out. A fouled plug will have a velvety black electrode and could be wet with fuel and will smell like gasoline. We had a car at the shop a couple weeks ago that was misfiring real bad on a few cylinders. Changed the plugs and it didn't help at all. Finally changed the 02 sensors and it fixed the problem. Is your 02 old? They're only $20 so it couldn't hurt to change it out.

 

I haven't changed the 02 sensor but the mechanic tested it and said it was fine. I just came back from changing the plug wires. No difference. I am also really sick of taking out those plugs. Do you think it might have something to do with my MSD ignition? I have a blaster 2 coil which is different than the stock 2 plug coil. But I kinda felt the misfiring a little bit before I put the MSD in.

 

When I had my L03 in the car still, I tried an MSD coil. It misfired pretty bad. I had to put the stock one back in it. Try that.

 

Has it worked with the 58mm TB on there? How long have you had the mods you have, with the current probably? Just recently? Or most of the time..Have you tried decreasing the plug gap? I'm not sure what spec is on '91, but I know it's a bit lower on mine. Just some thoughts..

 

I had the Holley FI setup since December an it ran awesome. I tried the stock coil and even disconnected the MSD ignition. Same thing. And the gap stock is 50 but MSD recomends increasing the gap by 10 when installing their ignition.

 

Do you think it may just be a bad ignition box?

 

its ignition or fuel related. spark fuel compression right?

if its running good at all other places on the fuel map (and it is if i read correctly) then theres somthing going on with the fuel, or spark at WOT.

could be ignition breaking up, could be too much timing (Jet Chips are notorious...) could be knock, could be running lean (02 sensor does not work at WOT, fuel map could be lean, again JET chip)...

could be somthing hardware related like the ignition module or coil or even the distributor cap.

I dont see any engine mods, if your motor is taking in a significantly bigger amount of air during WOT than when it was factory stock the fuel map would definetelly be lean up there. everywhere else there is 02 trim during closed loop.

have you tried octane booster? that would point towards timing if the octane booster helped out a lot. it could also point towards a weak spark. its very possible your MSD coil cannot handle the plug gap, I dont see MSD6al anywhere and your gaps should not be .060 unless you have a CD ignition, i dont think. Its very easy to "blow" out a spark when using a very large gap. I used splitfires for a long time with a blower so they are not a very hot heat range, worked pretty good and im still using them, I run a .050 gap because of the cylinder pressures from the blower, but i also have a 6AL-BTM to back it up.

what do your plugs look like?