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Engine Specific Info and Questions => IDI Engine => Topic started by: sean_caton666 on November 07, 2015, 02:41:56 pm

Title: 1.6td idle drop
Post by: sean_caton666 on November 07, 2015, 02:41:56 pm

I was driving down the road and was coming to a stop sign. I took the car out of gear and as soon as i did the idle dropped down to about 350 rmp. I have no idea what is causing this. Could it be the head gasket? If I keep my foot on the gas its all good. Still starts right up, just the super low idle. Please help

Title: Re: 1.6td idle drop
Post by: vanbcguy on November 07, 2015, 07:07:01 pm

Any air bubbles in the feed line to the pump? Have you tried adjusting the idle speed?

Title: Re: 1.6td idle drop
Post by: libbydiesel on November 07, 2015, 08:20:02 pm

Quote from: sean_caton666 on November 07, 2015, 02:41:56 pm

Could it be the head gasket?

I'm not going to say it's impossible that a low idle would be caused by a head gasket issue, but I've never seen or heard of it.  Most common cause I've seen is that the idle screw locknut has vibrated loose and the idle has adjusted itself. 

Title: Re: 1.6td idle drop
Post by: sean_caton666 on November 08, 2015, 10:47:27 am

thanks you guys ill check on that stuff today

Title: Re: 1.6td idle drop
Post by: air-cooled or diesel on November 08, 2015, 01:50:50 pm

id say in this situation, unless idle screw locknut came loose, its either air in inlet/pump, or try changing out fuel filter, prime from inlet

Title: Re: 1.6td idle drop
Post by: sean_caton666 on November 09, 2015, 03:10:15 pm

there is air in the line, would a new fuel filter take care of this?

Title: Re: 1.6td idle drop
Post by: Dakotakid on November 09, 2015, 08:53:13 pm

Probably not. What shape is the fuel line (which connects to BOTH sides of the fuel filter) in. Over the years, they tend to crack on the inlet side.

Also, have you removed the old plastic fuel separator box ahead of the passenger front wheel (bottom of car)? THOSE suck air as the plastic breaks down. I just removed my last one (off a car which has been sitting out of service for several years) last week. This is a common problem and you need to address it before it leaves you stranded on the road or in a bad part of town (where you score yer junk?).

Title: Re: 1.6td idle drop
Post by: sean_caton666 on November 11, 2015, 12:30:03 pm

did you just remove it, or replace it?

Title: Re: 1.6td idle drop
Post by: fatmobile on November 11, 2015, 02:45:16 pm

Water separator gets removed and replaced with a piece of 5/16" metal tubing.
 Remove the check valve in the line after it too.
 The tank will drain if you remove the hose because it's lower than the tank.
 You'll need to check the fuel pickup screen too, check for clogging.
 Do that first so the fuel line is disconnected from the water separator.

 Then change the filter, ha.