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> 73 2.0 djet idle problem
jasons
post Mar 19 2007, 09:22 AM
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Car is a 73 2.0, new TPS, new FI Points, new TS1, existing TS2 (its the 017), all intake runners, hoses, gaskets, and PCV are new, injectors were cleaned and serviced by witchhunter. Also all parts are correct for the 73 2.0. I put a 270ohm resistor in too. Car seems to run lean at idle (I have an air fuel meter).

I had the wrong TS2, because I replaced it with what I thought was the correct replacement. Upon further review, I put the used 017 piece back in.

The car had been sitting when I bought it, so I dropped the motor to take care of a few problems, and I refurbed the FI while I was at it.

Car seems to have good power and pull hard, but it doesn't seem to idle quite right. It oscillates between, 1000 and less than 500, while the air meter reads lean. Air bleed and the knob both effect idle, but I can't get it to stabilize or richen up on the meter.

Also, I have a euro-race header and MSD. Should I play with the resistor or the FPR to richen the car for these parts?
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pbanders
post Mar 20 2007, 05:41 PM
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We've been through this drill about a million times, but we gotta do it again...

Many of the problems associated with the FI system are often the result of some other underlying condition. Before you do anything on the FI system, you have to make sure that:

1. The engine is in good mechanical condition - proper compression, proper valve adjustment, good intake manifold vacuum, no vacuum leaks, hoses plumbed properly, no vacuum leaks, all systems in place (e.g. PCV valve system in place and valve working properly)
2. The electrical system is in good condition - battery at proper voltage (at least 12.75V for a fully-charged battery with the engine off), charging system in good condition (13.6V to 14.0 V when idling). All grounds in good condition, and full charging system in proper order - voltage regulator, alternator, battery, and cables. EXAMPLE - I'm fighting an idle stability problem with my car right now that I have traced to a bad alternator, that produces an oscillating idle when I have the lights on - looks just like a lean condition instability.
3. Fuel supply and pressure are good - must provide the proper output and be dead-on the factory pressure of 2.0 bar
4. Ignition system in proper working order - plugs, wires, coil, cap, rotor all new or flawless, plugs properly gapped, timing and dwell spot-on, dizzy mechanical advance in proper working order, points plate moving smoothly, vacuum retard cell operating (essential for proper idle operation), vacuum advance cell operating (if on a '73 TB, otherwise, plug it). If you have Crane/MSD/Pertronix, set up according to the manual.
5. FI system bits all the right part numbers and working properly - check my web page for info. TPS properly adjusted so that the idle switch is actuated when you close the throttle, throttle stop set so that you get a full 20 clicks when you open the throttle, MPS in good shape - either properly calibrated by someone on the list with the tools and know-how, or an OEM unit that hasn't been tampered with (or a rebuilt that's been checked out). Pull the ECU plug and check all the parameters at the plug with a DMM (procedure described on my web page).
6. FI idle mixture set to spec - on most D-Jet 1.7 or 2.0 L motors, this means setting it to 3.0 %. To do this properly requires a shop-quality air/fuel gauge, an IR-dispersive one at a minimum, or a 5-gas analyzer. You should be able to get a local shop to do this for you for cheap, it takes a few minutes - make certain the car is FULLY WARMED UP when you do this (i.e. run for at least 30 minutes prior to the measurement). Once the mixture is set, set the idle to 950 rpm with the bleed screw.

If you still have a problem at this point, then the troubleshooting can begin.
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jasons
post Mar 20 2007, 06:16 PM
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Brad, I can't tell you how much time I have spent on your site educating myself and verifying my setup. (IMG:style_emoticons/default/pray.gif) I think I've done a pretty good job refurbing this car that sat dead for like 5 years in the PO's garage. So please bear with me, I'm not the typical clueless guy wading through cracked and dry parts on his tired old DJET. I'm real close to having this car dialed, I just need a little expert advice.

The unknowns of your list, I accented in red as a matter of record, the one that stands out is the dizzy retard.

QUOTE(pbanders @ Mar 20 2007, 04:41 PM) *


1. The engine is in good mechanical condition - proper compression, proper valve adjustment, good intake manifold vacuum, no vacuum leaks, hoses plumbed properly, no vacuum leaks, all systems in place (e.g. PCV valve system in place and valve working properly)


Compression is good, valves are adjusted, haven't tested vacuum tested for leaks, all hoses new including runners, plumbed absolutely correct, brand new PCV.

QUOTE(pbanders @ Mar 20 2007, 04:41 PM) *

2. The electrical system is in good condition - battery at proper voltage (at least 12.75V for a fully-charged battery with the engine off), charging system in good condition (13.6V to 14.0 V when idling)


I checked the charging system and it appeared good, but I will double check it tonight

QUOTE(pbanders @ Mar 20 2007, 04:41 PM) *

3. Fuel supply and pressure are good - must provide the proper output and be dead-on the factory pressure of 2.0 bar


Set the fuel pressure last night to just under 30lbs. My gauge doesn't read Bar. Also my injectors are all tested and serviced by witchunter. New SS fuel lines and all new FI hose otherwise.

QUOTE(pbanders @ Mar 20 2007, 04:41 PM) *

4. Ignition system in proper working order - plugs, wires, coil, cap, rotor all new or flawless, plugs properly gapped, timing and dwell spot-on, dizzy mechanical advance in proper working order, points plate moving smoothly, vacuum retard cell operating (essential for proper idle operation), vacuum advance cell operating (if on a '73 TB, otherwise, plug it). If you have Crane/MSD/Pertronix, set up according to the manual.


New Plugs, New Magnecore wires, newer coil, cap, and rotor. Gapped at .028. Pertronix so no dwell. Advance plate checked out and ground wire appears good. My retard cell is dead! doesn't hold vacuum MSD is set up correct. I sent my schematic to an MSD tech to verify before install.

QUOTE(pbanders @ Mar 20 2007, 04:41 PM) *

5. FI system bits all the right part numbers and working properly - check my web page for info. TPS properly adjusted so that the idle switch is actuated when you close the throttle, throttle stop set so that you get a full 20 clicks when you open the throttle, MPS in good shape - either properly calibrated by someone on the list with the tools and know-how, or an OEM unit that hasn't been tampered with (or a rebuilt that's been checked out). Pull the ECU plug and check all the parameters at the plug with a DMM (procedure described on my web page).


All parts are correct for a 73 2.0. I checked everything when the motor was out of the car. Brand new TPS adjusted correctly when I had the motor out. I'll have to check the 20 clicks, MPS is an X factor it holds vacuum, hasn't been tampered with, and is correct for 73 2.0 I tested the harness and parts when the motor was out.

QUOTE(pbanders @ Mar 20 2007, 04:41 PM) *

6. FI idle mixture set to spec - on most D-Jet 1.7 or 2.0 L motors, this means setting it to 3.0 %. To do this properly requires a shop-quality air/fuel gauge, an IR-dispersive one at a minimum, or a 5-gas analyzer. You should be able to get a local shop to do this for you for cheap, it takes a few minutes - make certain the car is FULLY WARMED UP when you do this (i.e. run for at least 30 minutes prior to the measurement). Once the mixture is set, set the idle to 950 rpm with the bleed screw.


I'm going to have to get to my friends shop to have access to a CO analyzer


The item that stands out first and foremost is the retard cell on my dizzy. It doesn't hold vacuum, so its not hooked up just capped off at the TB. Also I should be clear, I have no decel circuit parts. Can I use the vacuum retard canister that aircooled.net sells or do any of you FI guys have an extra one, correct for a 73 2.0?
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Posts in this topic
jasons   73 2.0 djet idle problem   Mar 19 2007, 09:22 AM
sean_v8_914   does yoour ECU have the mixture potentiometer?   Mar 19 2007, 09:37 AM
jasons   does yoour ECU have the mixture potentiometer? ...   Mar 19 2007, 09:44 AM
Demick   First thing - unless your O2 sensor is a wideband ...   Mar 19 2007, 11:35 AM
jasons   First thing - unless your O2 sensor is a wideband...   Mar 19 2007, 12:04 PM
Demick   Relocated fuel pump shouldn't cause any issues...   Mar 19 2007, 12:07 PM
2-OH!   Run the engine to operating temp...At this point, ...   Mar 19 2007, 02:12 PM
jasons   I did time it, but that was when I was using the...   Mar 19 2007, 02:18 PM
bob174   You do have a good MPS right? Have you pulled a v...   Mar 19 2007, 08:01 PM
jasons   You do have a good MPS right? Have you pulled a ...   Mar 19 2007, 08:56 PM
Bleyseng   You do have a good MPS right? Have you pulled a ...   Mar 20 2007, 08:37 AM
jasons   When I had the motor out I checked all the parts a...   Mar 20 2007, 09:13 AM
Bleyseng   When I had the motor out I checked all the parts ...   Mar 20 2007, 04:38 PM
jasons   When I had the motor out I checked all the parts...   Mar 20 2007, 04:51 PM
Dave_Darling   Low fuel pressure will cause a lean condition. Tr...   Mar 20 2007, 09:33 AM
jasons   OK so bumping the Fuel Pressure didn't make a ...   Mar 20 2007, 03:56 PM
pbanders   We've been through this drill about a million ...   Mar 20 2007, 05:41 PM
jasons   Brad, I can't tell you how much time I have sp...   Mar 20 2007, 06:16 PM
Bleyseng   Have you checked for vacuum leaks at the usual spo...   Mar 20 2007, 09:55 PM
jasons   Have you checked for vacuum leaks at the usual sp...   Mar 20 2007, 10:34 PM
Bleyseng   How much is the timing mark "walking"? m...   Mar 20 2007, 10:40 PM
jasons   How much is the timing mark "walking"? ...   Mar 20 2007, 10:44 PM
Bleyseng   There is some up/down play but there shouldn't...   Mar 21 2007, 12:02 AM
jasons   There is some up/down play but there shouldn...   Mar 21 2007, 08:37 AM
Gint   The Pertronix should have cured *minor* distibutor...   Mar 21 2007, 08:47 AM
jasons   OK so, I installed the new vacuum pod and un-delet...   Mar 21 2007, 11:11 PM


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