Hesitating & Backfireing and Engine light comes on

Since it is so old, Start with a compression test. 90lbs is about minimal. The cylinders should be with in 10% of each other. If your there or lower, Time to retire or rebuild this engine. This part here will save you time, trouble and money into an engine that won't be any better when your done.

Has to be diagnosed at a repair shop

Surely you don't think someone without
the vehicle to test ,can guess at what is
wrong with it

if it has the brake lights as well for the ABS then i suspect a faulty computer ,end of story

okay i have the same problem sometimes it will start ok sometime it will not so had to put a rag in the air filter with gas on the rug to starts it but it does alot of hesitating when you're driving it. it just started doing hesitating now its doing this idoling up and down and when you crack it over alot the check engine light come on when it running but eventually it tunes off i was thinking about changing the fuel filters again to see if thats the problem because i think it started when i change the fuel filter i need a little help

Sounds like the timing is off a bit!

I believe this is a fuel injected engine, not a carburetor engine.

Having said that, given what you've already checked and believe to be OK, I'd take a look at timing if I were you.

Could be a timing chain has either loosened or broken, allowing camshaft to get out of time relative to crankshaft. This could cause the backfire you describe.

However, before you go that far....after putting in the new plugs are you positive you got the spark plug wires correctly located ? Crossed wires could also cause a backfire.

Good luck!

ur timeings off or ur spark plugs need be change and gas filter 2 this stuff cause the motor to stall

engine can be out of time
low fuel pressure
or can be a burn valve
need to check ignition timing and fuel pressure to see if they are ok first

Ok, there are many issues here that you will need to inspect. I recommend changing the fuel filter and pump as well. this will fix the hesitation. the intake and exhaust manifold gaskets will need to be replaced as well. this will stop the backfiring.

I also recommend checking and running a teat on the PCV valve and inspect the PCV hose as well. it could have a leak or a small crack on it.

Check the air filter and change if needed. this will help with acceleration issues as well. Next, i would run a check on all plugs and the complete wire set as well. change if needed.

Inspect the injectors for leaks and lose wires. make sure they are in good condition. replace any injectors that isn't firing properly.

Ok, there are some sensors that you will need to check as well. i will list them below.

SENSOR CHECK LIST--

1. Check the O2 sensors for worn wires.
2. Check the MAFS(Mas Air Flow Sensors) Check for Damaged, Loose, or Faulty Mass Air Flow Sensor or Circuit.
3. Check the Air Cleaner Temperature Sensor. this sensor could be damaged ro have loose wires. check accordingly.
4. Check the Throttle Position Sensor. this device could be connected wrong or it may be faulty as well. replace if needed.

Be sure and inspect all the above and repair any problem spot you ruin across during your inspection.

Please rate and god bless:)

try disconnecting the maff sesor