1992 Dodge Dakota hard starting/miss/backfire

Hi:
A stuck EGR valve can cause the type of problems you described. Remove it and make sure it is functioning properly and there is no carbon build-up under it.

Let me know what you find.

Joe

I checked EGR and it is working properly. What it be now? I should mention that when it backfires,it is backfiring through the intake. Since I posted the original question the idle quality has gotten worse. And the hesitation is around 2,000rpm's. If you could point me in the right direction it would be great.

Hi Again:
You could try the O2 sensor, but it could also deal with the map sensor, knock sensor... I hate to say it, but you may have to take it to a mechanic, or you will end up replacing part after part until you hit the right one. It may get expensive.

Hello,I have replaced the O2 sensor and the map sensor along with a new throttle position sensor. The truck idles now and starts great,but when you mash the gas it spits and sputters and backfires through the intake. If you give it steady acceleration it will run fine right up to the limiter. Any ideas? The sooner you can get back to me the better as this is going to be my only form of transportation soon. I appreciate your time and your insight.

Ok:
This is a tough one. Have you checked for vacuum leaks? Also, make sure the throttle body is tight to the intake.

As far as email, I'm on the site at least once a day to check mail, so I'm here for your questions and responses. If you're on tonight, I'll be here for about another hour. It's 8:00 in Pittsburgh.

Joe

Hello, I checked for vacuum leaks and I replaced the gasket under the throttle body. I noticed when I started it this morning it idled rough,like it was loading up,sounded like it had a oversized cam(lopey). I live in iowa and the weather was cold and damp this morning. After running for a minute it smoothed out. I'm at a lost,and anything you can give me would be a great help. Could it be the cam position sensor? Maybe fuel pressure regulator,fuelpump? Maybe a bad injector? I checked for codes and there are none. HELP!!

I would tend to feel that an injector would be all of the time. It wouldn't hurt to check the fuel pressure. You can rent a tool at most nationally recognized parts stores. Also, it could even be a weak coil.

I hate throwing all this at you because I can't be 100% sure, and I don't want you to spend money on parts that don't need replaced.

I'm going to email this problem to a friend that is a tech here. He worked for a chrysler / jeep dealership and is a great mechanic. Let me see if he has ideas.

Joe

let me ask when was the last time a complete tune-up was done meaning plugs, cap, rotor, wires also having timming checked

I replaced the plugs,wires,cap and rotor about a year ago. I don't put alot a miles on it,I'm guessing around 10-15 thousand,never checked timing.

ok now pull distributor cap off and have someone crank engine and see if rotor turns if so the check ingition module on bottom of distributor

I don't understand where you are going here? The truck starts and runs. It has a hesition now or a flat spot in the acceleration. With steady pressure on the gas pedal it will run ok. You mash down on the gas and there is a dead spot and it starts to pop and bang,spit and sputter. And will die if you don't let back up on gas.

ok do a compression test and let us know what you get on all cylinders and your code 21 TPS voltage was above 2.5 volts for 8 seconds when the MAP sensor signal showed manifold vacuum to be 15 pounds or more. and the code 32 EGR open command did not change the fuel mixture when the command was given during off idle operation. EGR opening should cause the mixture to be slightly richer because of the low oxygen content of exhaust gas. but do compression test also check the firing order is as follows Firing order 1-6-5-4-3-2 | 2 4 6 | front | | | | | | 1 || | |2 6|| of | |3 5|| | | 4 || | | vehicle | | | 1 3 5 | Distributor rotates clockwise Inspect the ignition coil for arcing while the engine is running. If the engine will not start, this can be performed while the engine is cranked by either an assistant or a remote starter. Look at the coil in dim or low light to aid visibility of any arcing. Arcing at the tower will carbonize the wire boot, which, if it is connected to a new ignition coil, will cause the coil to fail. In such cases, clean all the carbonization away or replace the components as necessary.

I check compression and everything is alright there. All cylinders had 90-95,and the ignition is wired correctly and as far as coil,everything looks good,didn't check resistance. i also,checked fuel pressure and with ignition in "on" position it had 15psi and with running it had 20psi,but the needle bounced around between 19.5-20.5psi,also when I hit the throttle it dropped to 15psi. And I should also mention that the pressure would drop down to 5-10psi after the engine was shut off and was sitting for a minute or two.

fuel pressure should be 37-41 PSI(Pounds per Square Inch) compression should be 100 psi +or- 8% 92 min. and 108 max. I would look into checking the fuel filter and or pump