 My 2.0 D-Jet motor runs hot,, Edit - idle fixed, vacuum leak found |
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| Cevan |
 Apr 14 2009, 11:34 AM
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Senior Member  Group: Members Posts: 1,079 Joined: 11-December 06 From: Western Massachusetts Member No.: 7,351  |
I swapped out my 1.8 L-jet motor for a stock 2.0 D-Jet motor. I’ve put about 75 miles on the car since the engine swap. According to my CHT gauge, it seems to be running hot. I had a similar problem with the old motor. That engine was running lean and I adjusted the AFM and got it to run around 325-350 on the highway (70-75 mph).
The 2.0 motor runs around 350 in 3rd or 4th gear at 3000 rpms and goes up from there when it’s on the highway. The gauge is definitely reading hotter temps across the board compared to the 1.8 motor. The only issues I have currently are a minor vacuum leak (idle is a bit high) and a TPS that is a bit worn. The car runs great otherwise. It accelerates nicely (noticeable improvement over the 1.8). All the tin is in place, fan is intact, no blades missing. Dwell and timing are correct. Valves adjusted. Injectors cleaned and tested. MPS good and is the correct one for a ’74 2.0 motor. New points, cap, rotor, plugs, plug wires, vacuum lines. I need to pull a plug and see if I see signs of it running lean. This is what I suspect. I will also check the fuel pressure. Could this be a timing issue? Could it run cooler at a different timing setting than the factory spec? Any thoughts? (IMG:style_emoticons/default/confused24.gif) I also can't get the idle below 1300 rpms. I have the idle adjustment screw all the way in and when I go to turn the idle mixture screw on the ECU CCW to get it below 1300-1400 rpms, it does this up and down thing with the revs. I've sprayed of starter fluid at every place a vacuum leak might exist and the revs don't change. I'm this close to putting L-Jet on the damn thing. |
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| r_towle |
Apr 20 2009, 07:26 PM
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Custom Member Group: Members Posts: 24,705 Joined: 9-January 03 From: Taxachusetts Member No.: 124 Region Association: North East States 
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you are running lean and the idle is high.
You have a vacuum leak. I just put new head breather hoses on..I used 7/16 rubber fuel line. Its tighter than the metric stuff (the correct size is 12mm) I also used clamps. Made it idle lower and perfectly smooth. I also adjusted the valves. Do you have a dwell meter? is that set right? Timing...its set different than Ljet...its set at 3500 rpm's. Rich |
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| Cevan |
Apr 20 2009, 08:36 PM
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Senior Member Group: Members Posts: 1,079 Joined: 11-December 06 From: Western Massachusetts Member No.: 7,351 |
QUOTE(r_towle @ Apr 20 2009, 09:26 PM)  you are running lean and the idle is high. You have a vacuum leak. I just put new head breather hoses on..I used 7/16 rubber fuel line. Its tighter than the metric stuff (the correct size is 12mm) I also used clamps. Made it idle lower and perfectly smooth. I also adjusted the valves. Do you have a dwell meter? is that set right? Timing...its set different than Ljet...its set at 3500 rpm's. Rich Yes, I have a dwell meter. Dwell is at 48. Timing is good. The head breather hoses are connected to the airbox, not the plenum so those shouldn't impact idle, right? I unplugged the hose going from the airbox to the 3-way connector and there was no change in idle. All those hoses are new. I've verified the AAR functions correctly. I guess I will check the valves again. Can't hurt, right? |
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Posts in this topic
Cevan My 2.0 D-Jet motor runs hot, Apr 14 2009, 11:34 AM
jsayre914 silly thing to check, did you try pushing the thro... Apr 14 2009, 06:43 PM underthetire Did you check the distrib. plate? Mine stuck once... Apr 14 2009, 06:54 PM
Cevan
Did you check the distrib. plate? Mine stuck onc... Apr 14 2009, 07:28 PM perrin1097
[quote name='underthetire' post='1157963' date='A... Apr 20 2009, 10:03 PM r_towle check the plugs....number 3 is key.
If you find i... Apr 14 2009, 08:21 PM Cevan
check the plugs....number 3 is key.
If you find ... Apr 15 2009, 05:40 AM SLITS The only D-Jet setup with a resistor was the ... Apr 15 2009, 06:38 AM Cevan
The only D-Jet setup with a resistor was the ... Apr 15 2009, 02:19 PM SLITS I cooled one down by simply having it on a rack. ... Apr 15 2009, 05:02 PM Cevan I had this motor apart down to a long block. The ... Apr 15 2009, 05:17 PM r_towle relax...
So, you have all the correct numbers so a... Apr 15 2009, 08:57 PM r_towle Let me try this so you can start hunting.
I will ... Apr 15 2009, 09:13 PM Cevan
Lets say there are three air fuel maps, hard code... Apr 19 2009, 07:22 AM 76-914 A leaky decel valve could be your culprit. Block i... Apr 15 2009, 10:02 PM Cevan
A leaky decel valve could be your culprit. Block ... Apr 19 2009, 07:23 AM r_towle Well,
You still have a vacuum leak if it idles tha... Apr 19 2009, 08:26 AM Bartlett 914 Another source of a vacuum leak it the air plenum ... Apr 19 2009, 09:12 AM Cevan Quick update: car still runs hot and no idle below... Apr 20 2009, 07:12 PM r_towle well, its running lean.
I cant accept that there i... Apr 20 2009, 09:46 PM orange914
well, its running lean.
I cant accept that there ... Apr 20 2009, 11:22 PM Cevan Vacuum leak found: PCV valve. I pulled the vacuum... Apr 25 2009, 02:26 PM r_towle Glad you figured it out and did not give up and go... Apr 26 2009, 08:38 PM Cevan So can I just hook the gutless PCV (now just a por... Apr 27 2009, 10:20 AM SLITS PCV hooks to plenum ... generally hi vacuum area
... Apr 27 2009, 03:15 PM |
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