Dies at idle. help

[Xmindx34]

I bought a 1994 ranger with the 4.0 and a 5 speed 4x4 with a blown headgasket ended up being two headgaskets and two cracked heads replaced everything got it running yesterday and today I was letting it idle and it idled pretty rough around 500-700 rpms then eventually dies i haven't been able to check the codes I have no scanner but it runs fine while driving and everything. There is a connector at the back of the driver side head at the end of the plug ins for the injectors that I left unplugged because I didn't know where it connected to if anyone has suggestions on what to look for and what to do it'd be greatly appreciated.

 

[monstermazda]

Could have a vacuum leak

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[swynx]

i think that plug might be the cam shaft position sensor, it is between the 2 heads on the back of the engine. but im not 100% sure, if it is, let it be known that not all models used them, and i am running a 96 block with 94 parts and i dont run it. i have no issues.

as far as your idle id probably check the idle air control valve. its on the side of the throttle body. i would just unplug it and see if there is any change in idle at all. i would also mess with the throttle position sensor, unplug it as well. if there is no change, then the sensors are bad, has been my general consensus for trouble shooting. maybe try to turn the adjustment screw for the throttle body blade, see if that helps. although this would probably be a last resort as 700ish is about normal.

as well it could also be on 02 sensor issue.

also a vacuum leak should cause a higher idle, seeing as there is unmetered air entering the system

 

[Xmindx34]

Alright thank you I'll check it out and the plug is in the wiring harness with all the injector plugs and at the end there are 2 connectors that look like they run back towards the transmission and then that one that could be the cam shaft position sensor it plugs into the back side of the block? On the passenger or driver side? And i plugged the vacuum lines in to where I thought they went I could have got them mixed up does one of the lines go into the air box I plugged one in there but wasn't sure about if it should go there?

 

[swynx]

Alright thank you I'll check it out and the plug is in the wiring harness with all the injector plugs and at the end there are 2 connectors that look like they run back towards the transmission and then that one that could be the cam shaft position sensor it plugs into the back side of the block? On the passenger or driver side? And i plugged the vacuum lines in to where I thought they went I could have got them mixed up does one of the lines go into the air box I plugged one in there but wasn't sure about if it should go there?

the camshaft position sensor is literally, right in the middle of the back of the block just above the transmission, between both heads and directly behind the intake manifold (if that makes sense), you cant even tell what it is by feeling for it. but like i said California models were the only ones required to run it, and im pretty sure it only aids in quicker starts, maybe some additional timing adjustments.(not 100% sure on that). your plug will be square. likely that other plug is the passenger side 02 sensor. it hooks up right behind the engine, and is a pain to get to.

look here, first post, this is my 94 engine. clear view of the camshaft position sensor.

http://www.therangerstation.com/forums/showthread.php?t=150472&page=3

as for the vacuum lines, every box i have seen has 2 fittings on it for air lines, but i dont even run them, there just to confusing and it has better response without them. when i swapped my engine i must have lost one of the air lines that went to the box so i just capped off the extra air line posts on the intake.

the only lines i run are 1 going to the fuel pressure regulator, 1 going to the a/c blower motor setup, 1 going to the brake booster im pretty sure all the rest i deleted. so i only run 3 airlines on my engine. the rest i have capped off.

 

[Xmindx34]

Alright I'll check to see if mine has that sensor the plug I didn't connect is square I believe I'm not home for the weekend so it'll have to wait till Monday I'll check then and see what I find thanks for your help

 

[swynx]

Alright I'll check to see if mine has that sensor the plug I didn't connect is square I believe I'm not home for the weekend so it'll have to wait till Monday I'll check then and see what I find thanks for your help

it is a square plug, it might have a protrusion on one side, i cant exactly remember.

as for that other plug, you have 2 02 sensors, one on each bank. crawl under the pickup locate the passenger side exhaust manifold and look for a sensor on it. it will be the only sensor, it should be unplugged...

if it is unplugged and the drivers side is plugged in that could cause problems.