Fule Pump or Fuel Regulator? |
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Fule Pump or Fuel Regulator? |
chrispovoas |
Aug 7 2023, 12:03 AM
Post
#1
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Member Group: Members Posts: 61 Joined: 8-April 23 From: New Zealand Member No.: 27,285 Region Association: Australia and New Zealand |
Hi guys, so on my journey to get the engine running an pulling correctly I have done the following;
1) Tracked down all of the air leaks so that the engne stalls if i cover up the main air intake on the air box 2) Refurbed all 4 injectors 3) Replaced the ignition leads, Rotor and distributor cap 4) Installed refurbed AA Valve 5) Checked the spark on all leads 6) Installed new plugs However, the engine still performs / runs like its on 3 cylinders... Once the injectors were done the engine was running sweet.. Parked the car for 2 weeks, engine back to running like a pig.. All 4 plugs were quite black (even after only running for about 3 miles in total since they were installed), which shows all 4 are getting fuel but running very rich. If the electrics are good, then it must be fuel? Perhaps the Pump or regulator?.. Anything i can check / test by myself? as my driveway is steep and the car doesnt have the power to get up it to take it to a mechanic Cheers Chris |
Superhawk996 |
Aug 7 2023, 06:53 AM
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#2
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914 Guru Group: Members Posts: 5,886 Joined: 25-August 18 From: Woods of N. Idaho Member No.: 22,428 Region Association: Galt's Gulch |
Check cylinder head temperature sensor (CHT)
Check manifold pressure sensor (MPS). Both of these affect mixture. Either can cause an excessive rich condition. CHT is the most likely. MPS rebuild kits are available from Tangerine Racing. |
Superhawk996 |
Aug 7 2023, 06:55 AM
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#3
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914 Guru Group: Members Posts: 5,886 Joined: 25-August 18 From: Woods of N. Idaho Member No.: 22,428 Region Association: Galt's Gulch |
Brad Ander’s D-jet site is required reading and has all the information you need to test and troubleshoot components
https://members.rennlist.com/pbanders/djetfund.htm |
JeffBowlsby |
Aug 7 2023, 08:32 AM
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#4
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914 Wiring Harnesses Group: Members Posts: 8,529 Joined: 7-January 03 From: San Ramon CA Member No.: 104 Region Association: None |
Check cylinder head temperature sensor (CHT) Check manifold pressure sensor (MPS). Both of these affect mixture. Either can cause an excessive rich condition. CHT is the most likely. MPS rebuild kits are available from Tangerine Racing. ^^^Agree. It may be something else but verify functionality these parts first. You wil need a Mityvac hand pump and an ohmmeter. |
brant |
Aug 7 2023, 09:07 AM
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#5
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914 Wizard Group: Members Posts: 11,634 Joined: 30-December 02 From: Colorado Member No.: 47 Region Association: Rocky Mountains |
really start with the basics
its the only way to rule out some of the potential problems... verify fuel pressure adjust the valves verify timing but I also agree with then verifying the CHT and MPS |
chrispovoas |
Aug 7 2023, 11:48 PM
Post
#6
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Member Group: Members Posts: 61 Joined: 8-April 23 From: New Zealand Member No.: 27,285 Region Association: Australia and New Zealand |
Check cylinder head temperature sensor (CHT) Check manifold pressure sensor (MPS). Both of these affect mixture. Either can cause an excessive rich condition. CHT is the most likely. MPS rebuild kits are available from Tangerine Racing. Cheers! But how do i "check them"? can i do via a voltage check or is there another way? I think the running rich is an issue, but i dont think it would cause the car to have that much of a loss of power and running like a pig? |
chrispovoas |
Aug 7 2023, 11:49 PM
Post
#7
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Member Group: Members Posts: 61 Joined: 8-April 23 From: New Zealand Member No.: 27,285 Region Association: Australia and New Zealand |
Check cylinder head temperature sensor (CHT) Check manifold pressure sensor (MPS). Both of these affect mixture. Either can cause an excessive rich condition. CHT is the most likely. MPS rebuild kits are available from Tangerine Racing. ^^^Agree. It may be something else but verify functionality these parts first. You wil need a Mityvac hand pump and an ohmmeter. Thanks Jeff, was wondering how to check.... |
brant |
Aug 8 2023, 06:47 AM
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#8
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914 Wizard Group: Members Posts: 11,634 Joined: 30-December 02 From: Colorado Member No.: 47 Region Association: Rocky Mountains |
The link above is for brad anders website
Read it 3 times It explains all of the testing procedures and more Adjust your valves Check your fuel pressure Get a Haynes manual Check timing and spark plug order if you have touched them You have a lot of reading to do And a day s wrenching Let us know what you find Update……. Just re read your initial post I’m betting you have a spark plug wire in the wrong order Check your firing order did you pull the distributor... it could be indexed wrong... so check firing order by verifying the motor is on TDC and then look at the rotor under the cap…for that position to be plug wire for cylinder #1 (you can verify TDC and adjust valves at the same time) It’s almost always the last thing touched by an owner causing the problem Brant |
dr914@autoatlanta.com |
Aug 8 2023, 09:01 AM
Post
#9
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914 Guru Group: Members Posts: 7,890 Joined: 3-January 07 From: atlanta georgia Member No.: 7,418 Region Association: None |
what year and engine size?
Hi guys, so on my journey to get the engine running an pulling correctly I have done the following; 1) Tracked down all of the air leaks so that the engne stalls if i cover up the main air intake on the air box 2) Refurbed all 4 injectors 3) Replaced the ignition leads, Rotor and distributor cap 4) Installed refurbed AA Valve 5) Checked the spark on all leads 6) Installed new plugs However, the engine still performs / runs like its on 3 cylinders... Once the injectors were done the engine was running sweet.. Parked the car for 2 weeks, engine back to running like a pig.. All 4 plugs were quite black (even after only running for about 3 miles in total since they were installed), which shows all 4 are getting fuel but running very rich. If the electrics are good, then it must be fuel? Perhaps the Pump or regulator?.. Anything i can check / test by myself? as my driveway is steep and the car doesnt have the power to get up it to take it to a mechanic Cheers Chris |
chrispovoas |
Aug 8 2023, 10:05 PM
Post
#10
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Member Group: Members Posts: 61 Joined: 8-April 23 From: New Zealand Member No.: 27,285 Region Association: Australia and New Zealand |
The link above is for brad anders website Read it 3 times It explains all of the testing procedures and more Adjust your valves Check your fuel pressure Get a Haynes manual Check timing and spark plug order if you have touched them You have a lot of reading to do And a day s wrenching Let us know what you find Update……. Just re read your initial post I’m betting you have a spark plug wire in the wrong order Check your firing order did you pull the distributor... it could be indexed wrong... so check firing order by verifying the motor is on TDC and then look at the rotor under the cap…for that position to be plug wire for cylinder #1 (you can verify TDC and adjust valves at the same time) It’s almost always the last thing touched by an owner causing the problem Brant Hi Brant.. Left it overnight and it spluttered into life.. I also thought the leads were on the wrong way round! but an overnights nap seems to have sorted the starting issue. Next step will be fuel pressure! Will let you know how i get on! Cheers |
r_towle |
Aug 8 2023, 10:12 PM
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#11
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Custom Member Group: Members Posts: 24,585 Joined: 9-January 03 From: Taxachusetts Member No.: 124 Region Association: North East States |
What year, engine, size, and fuel injection type?
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