Allpar Forums banner

1 - 4 of 4 Posts

·
Registered
Joined
·
2 Posts
Discussion Starter #1
Alright guys first I'll start by stating what I have.

1992 Dodge Shadow
2.5L
Automatic
No EGR

Here is what I have replaced so far.

Spark plugs, wires, air filter, oil change, cap, rotor, pcv valve, timing belt, water pump, thermostat, radiator, and I just recently had the head milled and installed a new head gasket.

I have no known vaccum leaks. My problem existed before and after I made all these repairs.

The car drives great and has plenty of power and I get decent gas mileage. I averaged 22mpg on a recent trip through the mountains.
So basically the car drives and idles great, except when you put it in drive. It shakes and vibrates the steering wheel and it iocassianly hiccups like it wants to shut off. But like I said once you are driving its perfect. It doesnt stumble on accelaration. I also failed emissions a couple of days ago. here are the numbers.

HC readind 0.19 standard 1.00
CO reading 4.48 standard 12.00
NOX reading 2.58 standard 2.50

You can see that it barely missed. anybody have any ideas? Thanks in advanced.
 

·
Super Moderator
Joined
·
21,364 Posts
Welcome to Allpar. Does it seem like the idle speed is too slow or just rough like cylinder misfire? Do you have a normal idle speed 'flare up' then drop to normal when starting (this can be used to test the IAC)? Is it worse hot or cold?
Does the 'ck eng' light come on when the ign is turned on and go out once started? Any fault codes? http://www.allpar.com/fix/codes/index.html
A scan tool (like the DRB II) can display target idle and actual idle. They should be close to each other when put in drive. The IAC steps should also rise when put in gear, or steering wheel turned all the way one way or the A/C compressor engages to reflect the added load and drop down when put back in neutral.
Is the PCV an OEM replacement? Any crankcase blowby 'mayonnaise' in the air cleaner or PCV box?
The catalytic converter has an element to reduce NOx that also may have failed.
http://www.longbeachmuffler.com/CatConvInfo.html
 

·
Registered
Joined
·
2 Posts
Discussion Starter #3
ImperialCrown said:
Welcome to Allpar. Does it seem like the idle speed is too slow or just rough like cylinder misfire? Do you have a normal idle speed 'flare up' then drop to normal when starting (this can be used to test the IAC)? Is it worse hot or cold?
Does the 'ck eng' light come on when the ign is turned on and go out once started? Any fault codes? http://www.allpar.com/fix/codes/index.html
A scan tool (like the DRB II) can display target idle and actual idle. They should be close to each other when put in drive. The IAC steps should also rise when put in gear, or steering wheel turned all the way one way or the A/C compressor engages to reflect the added load and drop down when put back in neutral.
Is the PCV an OEM replacement? Any crankcase blowby 'mayonnaise' in the air cleaner or PCV box?
The catalytic converter has an element to reduce NOx that also may have failed.
http://www.longbeachmuffler.com/CatConvInfo.html
The idle speed does not seem too low. When I start the car it does flare up. Temperature doesnt seem to affect it. Check engine light comes on with the ignition switch, but i have no codes. The air cleaner is clean and yes the pcv valve is oem. This is driving me crazy, would ignition timing cause this?
 

·
Super Moderator
Joined
·
21,364 Posts
The 2-wire coolant temp sensor at the thermostat has to be unplugged in order to set ign timing. This will turn on the ck eng light, but that fault can be cleared after setting timing. If you have an advance timing light, set the flywheel mark to 0 and shine the light in the top cover cam timing plug hole for a cam timing check. The cam sprocket index oval should be centered in the hole with the timing flash.
If everything engine-wise checks out OK, a metal to metal contact at a misadjusted or collapsed rubber motor/transaxle mount can transmit a large amount of engine vibration into the car body. This may not be there until the motor tips back in Drive. A bent or sagged cat can also hit the crossmember frame in Drive. In Reverse, the engine would tip forward and lift the cat.
The right (passenger) side and center (front) mounts are adjustable. A shiny 'witness' mark on the metal portions would prove that metal contact is taking place. A prybar can move things over or tipped forward about an 1/8", enough to clear the contact problem.
 
1 - 4 of 4 Posts
Top