Check engine light on and RPMs keep jumping

I would personally start with plugging in an OBD scanner and figuring out what the check engine light is on for. Be a good starting point!

 

Ya should get the code

 

Well if it goes haywire when the CEL comes on, then more than likely it's directly related to that code. I would check it out.

Other than that, my old 95 n/t act nutty as sh** like you're talking about when the rear o2 sensor had the wiring to it ripped out by something snagging on it.

 

Usually in my experience when the rpm gauge go on the, fritz like that its the crank sensor. On your 420a you need to change your crank & cam sensor. This will solve your problem. Use OEM only from the dealer.

Had a pt cruiser with a problem go through 4 different part store cam sensors and when a oem dealer sensor was used it solved the problem.

 

Why did you have the cam and crank sensors changed a month ago? And did you get the parts from the dodge/chrysler dealer or parts store?

And no not really with the CEL. When it goes off ecu is not sensing/compensating for the problem. Had this happen with a lincoln b4. Car misfire real bad under a load. Once the ecm notice enough off it it would flip the CEL and switch to a limp mode where it would run fine. You need to look up that code if pssible.

 

if the cam and crank sensors dont come up in the scan check out the idle air control valve.

 

First off guys, unless he can track down something to scan OBDI, he won't be pulling any codes he's got a 95. He needs to do the key dance. BlueNinja is on the right path. It sounds like whatever the problem is, when the CEL kicks on, it's going into limp mode, so definitely look into your sensors.

 

My 95 is ODB2, I'm pretty sure all 2gs are ODB2.
Mine even has a 94 build date.

 

Sure isn't. It's got an OBDII port, but OBD2 were not put into effect untill 96. Hook up a scan tool and get back to me when it won't light up...

 

Here is a picture of my ODB2 scan tool hooked up to my 1995 2g (with a 1994 build date).
I just ran outside and took this picture.

 

Obd2 was required in all vehicles produced in 1996 and up. Mitsubishi and some other manufactures switched over early. If it has an obd2 port it is obd2. To the op: go get your car scanned.

 

thats cool, this is my OBD2 scanner, with wifi capabilities.

but on a serious note the computer giving you the code and you reading it IS the very first step, not ignoring it, why did you wait until the problem became mechanical... sheesh. some vehicles cut-off's/shuts down the sensor or the system once identified it has malfunctioned to prevent further failure. that's why it may not give you problems when the light is on. the ECU is a reactive system and not a proactive one. It will react/adjust to anything that GOES bad, not prevent it or foresee any possible problem.

 

Ok ok I get it.... jeezus. On a side note, I still don't believe you.

 

the technical name for 95-96 obd2 plug equiped vehicles is obd1.5.. some scanners work like normal and others you have to use the "universal/global" setting when you hook it up.

 

That's what I thought. I had a 95 that would not scan, checked all the pins and the plug worked fine. Hooked up a universal and whammo!

 

Yes, autozone still does it for free. Good luck man

 

It jumped time? Did you double check that there wasn't any damage to the valves before putting it back together?

On a side note; yes 1996 was the mandate for OBD2. However, some cars that were in the middle of a body redesign, got the early version of OBD2 in the model years before 1996. If I recall, it was "voluntary". I've seen that the early 4th gen f-bodies also were OBD2 compliant. Yet, my '95 Mustang is not. Figures. Then again, Ford still used the 302 until 1996, when the new "modular" engine was introduced into the Mustang, so maybe that's what they were waiting for...

 

Ignore the o2 for now and fix the egr problem first. Then once fixed drive to see if o2 code, comes back.

 

i would pull that O2 sensor out and if it is burned up replace it. up-stream o2 sensors affect air fuel ratio. also go back to autozone and have them pull up freeze data just to see if any other codes have ever caused the light to come on.

also the egr valve and solenoid are sold as an assembly, try a salvage yard or junkyard the solenoid comes off very easy and will save you lots of money this way.