Ok my car was a no crank no start at first it's an 89 formula 350 tpi I replaced starter a bunch of relays and all that ended up being the key reader in the ignition key cylinder, then the car would run but ran like it was misfiring on half the cylinders. I took it to a mechanic but he unplugged something from the ecm and now it runs fine except for when it's at 900-1200 rpm above that it's fine and below it's fine, it idles at 650-700 rpm
When I rev it up to 6000 it back fired when I let off, it was on stands for months and hasn't really be driven in like 4 months so I'm thinking timing, bad injector, or clogged injector that's unloading or charging idk but I've been told it just needs a tune up. I'm not fully convinced though that the no start and this arnt all related though a bad ecm it's a factory refurbished ecm so it's clearly Ben pulled before I've only had the car about 7 months any ideas?

 

Buy a timing gun. Backfiring is usually a sign of the timing being off.

 

Ok sounds like a responsible plan ha

 

Did you change it?

Then it's fine. Leave it alone, otherwise you just end up creating more work, since you'll just have to go back and put it back where it belongs once you find THE REAL problem.

If you changed it, put it back, NOW. Then lock it down and leave it alone.

I'd suggest a tune-up, cleaning the injectors, and stuff like that; IOW, work on things that CAN wear out and CAN go bad and CAN change all on their own, unlike "timing".

 

the timing can also be severely retarded and the engine will run like crap if the timing chain jumps a few teeth..

but, yeah, the first step is to get a timing light.. but maybe also dump a few gallons of fresh gas in it to see if that helps.

 

First step is LEAVE THE TIMING ALONE and fix what's ACTUALLY CHANGED about the engine.

Fresh gas is definitely a good idea. Since gas CAN go bad, UNLIKE timing.

 

Ok I'm going to do a tune up and get a timing light first before I change it and maybe some engine cleaner

 

Timing gun [light]???

Maybe before spending cash on a timing light, just do a FREE static timing test.

Send ME a check, if you want, for the equivalent of a timing light.

 

I don't really believe in coincidence and I've been driving it all day and it seems to run worse after a while when it's in that 900-1200 range idk I don't see how all this could just happen at once

 

Valve timing and spark timing are very different things. Timing chains do not "jump a few teeth". I mean I guess theoretically it's possible on a heavily abused very high mileage engine while it's snowing in death valley in july, but generally if the chain is able to move on the gears while the engine is running it's going to just fail catastrophically before it magically resettles onto the next tooth over.

 

What do you think it is?

 

I think is it not the timing.

Put that out of your mind and do some investigative troubleshooting.

Sounds more fuel-related.

What's the fuel pressure WHILE IT'S SCREWING UP? (not while sitting in the driveway idling normally and behaving fine, WHILE IT'S SCREWING UP)

 

Are you getting a service engine light?

 

Yup

 

Question?... I am having a timing problem and figure this is the best time to ask what my timing should be for my 89 gta 350 tpi... the person before me took the sticker off so Idk what it should be... hopefully someone can help please and thank you.

 

Okay if you have an SES light you need to check the codes. Unfold a paperclip and shove each end into the two top right plugs on your OBDI port.



Ports A and B need to be shorted together. Its above your knees on the bottom of the dash.

After you do that, turn the key to the ON position (do not crank) and note what codes flash. The SES light will flash a certain number of times, pause, and flash another number of times. Then a longer pause will separate that until the next code. All codes are two digit numbers. The numbers of times it flashes are the codes. If it flashes 3 times, then 4 times, then that's code 34. If it flashes 4 times and then 8 times, it's code 48. It will give a longer pause between flashes. Write these down. The codes are pretty standardized so you can google them but you can always repost them here.

Your timing should be at 6 degrees with the ESC plug unplugged. The ESC being unplugged is essential to even reading your timing, much less adjusting it. Worry about that later. Read your codes. They will likely tell you what is wrong.

Why on earth do you think it's a timing problem? Unless the timing has been mechanically changed, it is not a timing problem. If it hasnt moved, leave it alone. Just because you have a vague understanding of what timing is and how to adjust it does not mean that's the answer. These cars are a lot different than your grandpappy's truck. In those older cars that started domestic car culture, most problems WERE timing or just gunk in the carb. That's rarely the case anymore unless some idiot who thinks he is in 1970 is screwing around with your timing because he thinks that's what fixes things because that's what he used to fix things back in 1970.

Read your codes, we'll go from there.

 

I got -2,13,14, and 24

 

Now all it's showing is 12 also it will crank but hot start now

 

Because the process cleared the codes. 12 is a "handshake" code, it's saying "hello, diagnostic system is functioning, here's a 12, prepare for the rest of the messages"

12 System normal (ie functional)
13 oxygen sensor circuit open
14 coolant sensor high resistance or shorted
24 vehicle speed (vss) sensor circuit fault

Code 13: So you need to fix your O2 sensor which only affects closed loop driving. IE when the engine is up to temp and running. It wont affect how it runs when you first start it and it isnt up to temp yet. So if you're having warm temp issues, then that's part of it. If there's no O2 sensor the computer cant meter fuel and will resort to some pre-established "safe" table, which will likely make it run like poop.

A little background. When teh engine is cold the ECM just uses a generic table of fuel and spark to urn it. When it gets to temperature, it then reverts to a far more accurate and efficient tune. Closed loop just means it's using the O2 sensor to judge how rich or lean the Air/Fuel mixture is, and the ECM needs to be able to go into closed loop for the car to run the way it should. This can cause all kinds of backfires and running rich and so forth and so on.

Code 14 - CTS. This is a big deal. Clearly it's referring to the CTS going to the ECM. The ECM cant figure out how much fuel to send to the engine if it doesnt have the right temperature.

Sounds to me like the ECM has resorted to backup failsafe maps of fuel and spark timing, which means it will run, just badly. Replace the O2 sensor if the circuit is intact, and then check the CTS circuit. The CTS on a TBI car is right on the water neck. Its probably going to be very close to the throttle body/water neck for you as well. CTS failures are super annoying and will make the ecm think the car is in extremely cold weather and will therefore over-fuel the car. In many cases this will prevent the car from even idling. Sometimes it will make it so taht you have to hold the throttle way open to keep it running and it will "idle" at 3/4 throttle and 4000 RPM. Depends on how badly it has failed.

 

Well it will crank but not start now and the fuel pump isn't turning on when I turn the key

 

Do you have a multimeter? Have an FSM Factory Shop Manual?

 

A bad CTS will cause the fuel mixture to be wildly wrong and prevent the car from starting.

As far as the fuel pump... check the circuit and replace whatever is broken.