D-Jet troubleshooting |
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D-Jet troubleshooting |
saigon71 |
Nov 13 2009, 03:36 PM
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#1
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Advanced Member Group: Members Posts: 2,000 Joined: 1-June 09 From: Dillsburg, PA Member No.: 10,428 Region Association: MidAtlantic Region |
Could use some ideas…
Background: Car sat idle in a garage for six years - 37K miles. Engine was free. 2.0 factory d-jet. I adjusted the valves, installed a new fuel filter, changed the oil & put some gas in it. It fired up but had a very high idle. Since then, I have done the following: -New plugs & wires -New distributor cap, points & condenser (rotor was clean) -New air filter -New alternator & voltage regulator - tested good -All new vacuum lines from AA -New intake runner gaskets and manifold to head gaskets -Tested all FI components except the brain. Replaced AAR and MPS with good used ones, bench tested each before installation. MPS holds 20 in HG and electrical tests were within limits. Replacement parts are compatible based on this site: http://members.rennlist.com/pbanders/djetp...tm#troubleshoot -Tested fuel pressure - dead on factory spec of 2.0 bar -Dwell well within specs -Set timing dead on at 27 degrees BTDC with distributor lines plugged and disty at full advance - TPS set according to the picture I found on this site - New plenum to intake runner gasket - New cold start valve gasket - Tested PCV Valve - Plenum inspected – no holes found - Throttle body removed & thoroughly cleaned At all ambient temps tested (50-70 degrees F), the car fires right up but stalls almost immediately…this happens twice. Tapping the throttle does not help. On the third start, the car stays running and idle varies between about 800-1200 RPM. After about 10 minutes, it settles in at about 950RPM or so. Besides this, the engine runs great, has plenty of power and pulls hard in all five gears. Is this as good as it gets or am I missing something. Thanks in advance. Bob |
detoxcowboy |
Nov 24 2009, 06:50 PM
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#2
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Senior Member Group: Members Posts: 1,294 Joined: 30-January 08 Member No.: 8,642 Region Association: Africa |
Check Your timming? Oscillation w/ high idle can mean you have a leak where you do not expect it, I do not know what is in Auto Atlanta's vacummn line kit but...
Idle oscillates and/or idle is too high and cannot be adjusted down to 1000 rpm with the air bleed screw Vacuum leak Timing over-advanced Check the following areas for a vacuum leak: 1. Intake runner-to-head gasket/spacer 2. Injector seals 3. Intake runner boots 4. Air plenum (e.g. cracks or rust holes) 5. Throttle body gasket 6. Throttle body shaft (worn body or shaft) 7. Distributor vacuum adv/ret cell 8. Auxiliary air regulator (stuck open or leaky) 9. Deceleration valve 10. Manifold pressure sensor 11. Vacuum hose cracks 12. Cold-start valve gasket to plenum |
saigon71 |
Nov 24 2009, 07:15 PM
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#3
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Advanced Member Group: Members Posts: 2,000 Joined: 1-June 09 From: Dillsburg, PA Member No.: 10,428 Region Association: MidAtlantic Region |
Check Your timming? Oscillation w/ high idle can mean you have a leak where you do not expect it, I do not know what is in Auto Atlanta's vacummn line kit but... Idle oscillates and/or idle is too high and cannot be adjusted down to 1000 rpm with the air bleed screw Vacuum leak Timing over-advanced Check the following areas for a vacuum leak: 1. Intake runner-to-head gasket/spacer 2. Injector seals 3. Intake runner boots 4. Air plenum (e.g. cracks or rust holes) 5. Throttle body gasket 6. Throttle body shaft (worn body or shaft) 7. Distributor vacuum adv/ret cell 8. Auxiliary air regulator (stuck open or leaky) 9. Deceleration valve 10. Manifold pressure sensor 11. Vacuum hose cracks 12. Cold-start valve gasket to plenum Timing is spot on at 27 degrees BTDC. AA's vacuum line kit included every piece of vacuum line needed to replace all lines. 1. New 2. New 3. New 4. Inspected, no cracks or rust holes found. 5. New 6. Inspected, no excessive play 7. HOW DO I TEST THIS? 8. Replaced with bench tested used unit 9. Tested, will re-test 10. Replaced with bench tested used unit 11. All new vacuum lines & elbows installed 12. New gasket installed It looks like the only thing I missed on this list is: Distributor vacuum adv/ret cell - how do I test this. Thanks |
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