Backfiring & Smog - Please Help!
RonTruppa
10-08-2005, 03:00 PM
I live in California - and this car is a 3.0L 6cyl. 2B Carb - 85 Century with 65,000 original miles (old lady story), up for a Smog check LAST MONTH, so I have to fix it before the car's registration can be re-instated. My girlfriend needs it for work.
BACKFIRING - The car recently had a rough idle & backfired even though I replaced everything last year: plugs, wires, dist. cap, and rotor. Mechanic said dist. cap and rotor were cheap and needed to be replaced again. So I did that along with replacing the original coil - read that it could be faulty and misfiring with throttle (therefore BACKFIRING). Well, the idle is strong and back to normal, but the car is still BACKFIRING when pickup is needed on streets and especially highways. The guy at Autozone said it could be the timing, and he may be right because he told me to temporarily unplug the wire from the air filter box - and that works with an occasional backfire now. Obviously it's sucking up more gas now, and I won't pass smog with that unplugged, so HOW DO I FIX THE TIMING ON THIS CAR? Any other suggestions? Please help.
The SMOG PUMP (so I'm told) has needed to be replaced for about a year because the "Service Engine" light comes on shortly after a rattling/gurgling noise is heard coming from under the hood - I'm getting a "lean Oxygen" code. This only started happening when the engine overheated one day and the upper radiator hose emptied all the fluid over the engine compartment. The culprit was a worn out and cracked seal on the radiator cap (word to the wise). I replaced the EGR valve, most hoses, etc. The noise seems to be coming from the right side of the engine from this vent that looks like a car horn attached to a hose (driver's side), but the SMOG PUMP is on the left side, behind the radiator, being cranked by the belts. Is that the pump's vent on the right? Is it the SMOG PUMP that needs to be replaced? Any other suggestions?
BACKFIRING - The car recently had a rough idle & backfired even though I replaced everything last year: plugs, wires, dist. cap, and rotor. Mechanic said dist. cap and rotor were cheap and needed to be replaced again. So I did that along with replacing the original coil - read that it could be faulty and misfiring with throttle (therefore BACKFIRING). Well, the idle is strong and back to normal, but the car is still BACKFIRING when pickup is needed on streets and especially highways. The guy at Autozone said it could be the timing, and he may be right because he told me to temporarily unplug the wire from the air filter box - and that works with an occasional backfire now. Obviously it's sucking up more gas now, and I won't pass smog with that unplugged, so HOW DO I FIX THE TIMING ON THIS CAR? Any other suggestions? Please help.
The SMOG PUMP (so I'm told) has needed to be replaced for about a year because the "Service Engine" light comes on shortly after a rattling/gurgling noise is heard coming from under the hood - I'm getting a "lean Oxygen" code. This only started happening when the engine overheated one day and the upper radiator hose emptied all the fluid over the engine compartment. The culprit was a worn out and cracked seal on the radiator cap (word to the wise). I replaced the EGR valve, most hoses, etc. The noise seems to be coming from the right side of the engine from this vent that looks like a car horn attached to a hose (driver's side), but the SMOG PUMP is on the left side, behind the radiator, being cranked by the belts. Is that the pump's vent on the right? Is it the SMOG PUMP that needs to be replaced? Any other suggestions?
public
10-08-2005, 03:48 PM
Backfireing under load points to plug wires, cap, rotor, coil, or on later engines a coil pack. I have not been under the hood of an '85 in a while so I can't help with describing by location. You may want to check a Haynes or Chiltons manual at a parts store. It does sound like you are having fuel/air ratio issues which could be the smog pump. Good luck.
maxwedge
10-08-2005, 04:16 PM
mAybe it's time to take it to someone who knows how to fix this car???
RonTruppa
10-08-2005, 07:52 PM
Backfireing under load points to plug wires, cap, rotor, coil, or on later engines a coil pack. I have not been under the hood of an '85 in a while so I can't help with describing by location. You may want to check a Haynes or Chiltons manual at a parts store. It does sound like you are having fuel/air ratio issues which could be the smog pump. Good luck.
I've done all of the above myself (Wires to Coil pack - to save money that I don't have), but then I'd have a friend/mechanic check out my work - All good. It's interesting that you said it may be the SMOG PUMP. Is that possible NOW, even though it's been faulty for over a year? Do you think it's just starting to take it's toll? I've gotten pretty car savvy over the past few years, so you don't have to describe things to me - I didn't mean to sound green in my post, but I just don't know how to correct a car's timing. What is involved with that? Where do you begin? I'm going to change the SMOG PUMP in the next few days anyway (for smog check), but if it is the timing what do I have to look for?
I've done all of the above myself (Wires to Coil pack - to save money that I don't have), but then I'd have a friend/mechanic check out my work - All good. It's interesting that you said it may be the SMOG PUMP. Is that possible NOW, even though it's been faulty for over a year? Do you think it's just starting to take it's toll? I've gotten pretty car savvy over the past few years, so you don't have to describe things to me - I didn't mean to sound green in my post, but I just don't know how to correct a car's timing. What is involved with that? Where do you begin? I'm going to change the SMOG PUMP in the next few days anyway (for smog check), but if it is the timing what do I have to look for?
RonTruppa
10-08-2005, 08:02 PM
mAybe it's time to take it to someone who knows how to fix this car???
I can't afford to pay for a thorough check every time I bring it to someone, let alone the cost of having them fix it (I'm already up to $1000 spent on a $500 "worthy" car). So I'm turning to this forum, which has helped me out with it tremendously over the past couple of years, for some good sound advice that I'm capable of executing with my own hands.
I didn't mean to sound green, I'm not, I just need a new direction and I don't know what my next step should be (minus the expense of labor).
What's involved with "timing"? I've never done it before - eveything else has been at least looked over.
Thanks
I can't afford to pay for a thorough check every time I bring it to someone, let alone the cost of having them fix it (I'm already up to $1000 spent on a $500 "worthy" car). So I'm turning to this forum, which has helped me out with it tremendously over the past couple of years, for some good sound advice that I'm capable of executing with my own hands.
I didn't mean to sound green, I'm not, I just need a new direction and I don't know what my next step should be (minus the expense of labor).
What's involved with "timing"? I've never done it before - eveything else has been at least looked over.
Thanks
public
10-09-2005, 09:03 AM
Sorry, I should have paid closer attention to your first post.
To time it you rotate the distribuitor. It has a bolt in a slotted hole at the base. You will need a timing light or an "old shadetree" who can time it by ear. Also check the vacuum advance on the distribuitor.
To time it you rotate the distribuitor. It has a bolt in a slotted hole at the base. You will need a timing light or an "old shadetree" who can time it by ear. Also check the vacuum advance on the distribuitor.
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