Low rpm stumble |
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Low rpm stumble |
blitZ |
Aug 12 2009, 06:40 AM
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#1
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Beer please... Group: Members Posts: 2,223 Joined: 31-August 05 From: Lawrenceville, GA Member No.: 4,719 Region Association: South East States |
I had a Crane Optical, which recently died. I have replaced it with a set of points and condensor from my FLAPS (non-Bosch). The car runs fine except for a some stumbling at low rpms. It seems to struggle to get to 1800, then takes off as normal. I've double checked my point gap and timing. Any ideas?
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r_towle |
Aug 12 2009, 08:11 AM
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#2
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Custom Member Group: Members Posts: 24,591 Joined: 9-January 03 From: Taxachusetts Member No.: 124 Region Association: North East States |
non-bosch is your first problem, and it can be a bog problem.
The real parts cost under 15 bucks....get bosch RIch |
blitZ |
Aug 15 2009, 10:13 AM
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#3
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Beer please... Group: Members Posts: 2,223 Joined: 31-August 05 From: Lawrenceville, GA Member No.: 4,719 Region Association: South East States |
OK, I've replace the points and condensor with Bosch parts and still have the low rpm stumble. Even out of gear and giving it a little gas, it seems to struggle to 1800. After that it runs fine. I've double checked the timing, fuel pressure is correct. What else can I check?
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r_towle |
Aug 15 2009, 10:41 AM
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#4
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Custom Member Group: Members Posts: 24,591 Joined: 9-January 03 From: Taxachusetts Member No.: 124 Region Association: North East States |
FI or carbs?
Rich |
blitZ |
Aug 15 2009, 03:22 PM
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#5
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Beer please... Group: Members Posts: 2,223 Joined: 31-August 05 From: Lawrenceville, GA Member No.: 4,719 Region Association: South East States |
2.0, Djet
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r_towle |
Aug 15 2009, 06:07 PM
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#6
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Custom Member Group: Members Posts: 24,591 Joined: 9-January 03 From: Taxachusetts Member No.: 124 Region Association: North East States |
Three things to check and set.
Fuel pressure...get a gauge to test it inline before the pressure regulator. Check when the car is cold, and again when its hot. If it changes when hot and goes down...increase it by turning the bolt on the end of the pressure regulator and set the pressure to 28-32 when hot. Vacuum lines (I get sick of people that claim that this wont affect the car...it does, it does create a low idle issue) Check them and clamp them if you have any potential leaks. If you have the knob on the top of the ECU...where is it set? This is idle enrichment and if its cranked up to the max...you flood at idle. and finally, the TPS It needs to be set in a specific position, no other. It is only adjustable because the switch is used on alot of other cars..volvo, merc etc. So, open the cover, clean the gold contacts with di-electric cleaner and set it like the picture at idle. Rich Attached image(s) |
blitZ |
Aug 19 2009, 04:20 PM
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#7
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Beer please... Group: Members Posts: 2,223 Joined: 31-August 05 From: Lawrenceville, GA Member No.: 4,719 Region Association: South East States |
I've checked the TPS and filed the TPS reports. Adjusted the valves. Checked the dwell and timing yet again.
What else can be causing this? |
tod914 |
Aug 19 2009, 04:56 PM
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#8
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Advanced Member Group: Members Posts: 3,755 Joined: 19-January 03 From: Lincoln Park, NJ Member No.: 170 |
Have a coil you can swap out? Just replaced mine and made a world of difference.
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SirAndy |
Aug 19 2009, 05:11 PM
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#9
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Resident German Group: Admin Posts: 41,688 Joined: 21-January 03 From: Oakland, Kalifornia Member No.: 179 Region Association: Northern California |
What else can be causing this? What does your engine harness look like? I needed 3 spare harnesses to make one good one for my 1.7L. The wires get brittle, especially just inside the thick plastic shielding. I had to cut the thick plastic back about 1"-2" only to find a whole bunch of cracked wires. Also, check all your injector/brain grounds at the large ground connector block under the plenum. Lastly, plug wires and plugs. Get a ohm meter and measure each wire. Check the plug connectors. Check the plugs. (IMG:style_emoticons/default/shades.gif) Andy |
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