2004 Disco Hard start while hot

Payson

Active member
Aug 14, 2017
35
2
SOUTHERN CALIFORNIA
my 2004 disco II has recently developed a hot start shyness. At cold she fires right up, but after getting to temperature she takes considerable time to fire. I have cleaned the MAF, thinking that might be the culprit, but no real change. I have a fuel relay switch and crankcase sensor on the way, but am a little puzzled why/if heat would affect either of those. I see the d1's have a fuel temperature switch, but can't find any reference to one on the D2 in the workshop manual.

Any ideas?
 

rovercanus

Well-known member
Apr 24, 2004
9,643
244
sounds like the classic D2 crank position sensor going bad. If so your next symptom my be a rough idle.
 

JUKE179r

Well-known member
Sep 14, 2016
761
95
Suffolkshire, UK
I hope you got a Bosch crankshaft position sensor and not a Duralast.
I learned the hard way going cheap with a Duralast. I ended up stranded in a busy intersection.
 
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WaltNYC

Well-known member
Mar 3, 2010
707
135
NYC
sounds like the classic D2 crank position sensor going bad. If so your next symptom my be a rough idle.

+1. It is often reported that if you squirt some cold water on the body of the sensor, the truck will start more easily. Also, check the wires leading to the sensor for degradation from heat as they are close enough to the Y-pipe/Cat to be slightly burnt.
 

best4x4

Well-known member
Mar 1, 2015
595
72
Beaumont, TX
Duralast = can be a Bosch unit in the Duralast box. I’ve probably bought 8-10 CPS for D2’s in the past for D2’s I’m working on and only one of them was a no name unit vs Bosch. When it died I returned it, and got a Bosch unit in it’s place.
 

Payson

Active member
Aug 14, 2017
35
2
SOUTHERN CALIFORNIA
Well I did replace the CPS, but still have the same issue. I will look at the wiring closely to see if that is the problem. It seems to be getting fuel, and smells like, when it does start it's starting rich. Injectors?