K my car started to run like crap lately, getting 2.84 miles to the gallon and so I took it in to get it looked at and the timing was 20 degress advanced, my timing chain is slipping really bad, I need the injectors cleaned or replaced and I might have a burned valve, after the timing was lowerd down she runs like dying pos! how much is this going to set me back? The mechanic said I should sell it.

 

Did the mechanic disconnect the EST bypass connector BEFORE checking/adjusting the timing? Timing will generally be advanced 15-20° with the connector plugged together. Timing will usually be significantly retarded if the timing chain has slipped.

Maybe you should keep the car and trade-in the "mechanic".

 

How did you determine the valve(s) may be burned, injectors are dirty, or the timing chain has slipped? I'd seriously question the diagnostic skills of someone who cannot set timing correctly.

 

Timing chains don't "slip". Dismiss that idea.

A "burnt valve" will cause a massive combustion leak either into the exhaust, in which case you hear it as a loud "ffft-ffft-ffft-ffft" as the engine runs; or into the intake, in which case the engine will spit back into the intake every engine revolution, so you get "pop-pop-pop-pop-pop" in the intake. If your car isn't doing either of those things, you don't have a burnt valve. Dismiss that idea as well.

Learn to do simple maintenance on your car yourself. Sounds to me like it could use a set of spark plugs and a distributor cap and a rotor; and maybe an oxygen sensor. In other words, a tune-up. That usually takes care if bad gas mileage. If you do those things and it still doesn't run right, send the injectors to www.cruzinperformance.com and get them to clean and flow-match them.

Put the timing back where it was, no matter what the light (or the mechanic) said. Just put it back and leave it alone until you have the engine running correctly. Dinking around with it when it's not broken is a total waste of time. It doesn't just up and change all by itself; with the type of distributor these cars have, it could theoretically be set at the factory, and never need to be touched for the entire life of the engine. It isn't the cause of your problems, or at least, it wasn't until somebody narfed it.

An incorrect timing indication is very common. The timing mark is not connected metallically to the crankshaft. It is merely glued on loosely by a blob of rubber spooge, namely the outer "inertia" ring of the harmonic balancer. If the bond between rubber and metal fails, as it often does, your timing mark will be somewhere in the ozone, and then once you disturb it, there's no easy way to put it back where it belongs. That may have happened to you. In that case, you may need a new balancer.

 

She has brand new plugs, wires, cap, rotor, fuel filter, O2. Im assuming the timing was changed by the mechanic of the previous owner. Ive been doing my own maintnace but she just all of a sudden started to run ****ty and get 2.84 mpg. But thanks for the info, I didn't mean to sound like a moron thats never worked on his car, I droped it off at the shop because she has been seendingme a code 44 ( lean o2) and I just replaced that, and I thought maybe the computer was comensating for an intake leak I used to have, and throwing in more fuel but that would not make sense with the code 44 Ive been getting every so offten, it comes on and then the light goes away after awhile.

 

You might want to recheck the timing, inspect for vacuum leaks again, and clear the ECM so you're starting with a fresh slate.

Vacuum leaks can include the PCV, EGR, brake booster, a breather-type oil filler cap (diluting the fuel mixture), in addition to the more obvious hoses and gaskets. You might also want to check for air leaks into the exhaust system upstream of the O² sensor.

 

I'd recommend checking each injector's resistance--they should all be around 16 ohms and vary no more than 0.5-1 ohms.

I had a similar condition--poor mileage, ran crappy on my 1991 Z28 and this turned out to be the problem.

One more thing--if you need to replace one, replace them all. I wish I knew that then, I'd have saved ~$700.

 

If its a carbed engine, unplug the computer (connector is by the battery) and start it. Don't rev the engine, just let it idle and see how it runs. Is it better/same/worse? This sometimes help me to decide if its a computer issue or a mechanical issue. If it runs worse, its probably a mechanical problem. If it runs better, then its probably a computer-related problem.

 

Its TPI, thus the reason for injectors......

 

if it has that code it means the o2 is reading lean. check for exhaust leaks first! any at all even from the air injection sytem or bad gaskets,it may be getting air in there and the o2 see's this and tells the ecm to dump more fuel. the other thing that is very likely is the wire has a problem in its path from the ecm to the 02. grounding out some where. this would be most likely the cause before anything else

 

sorry, lol.

 

Thats ok lol