idling question.
Ajillag
09-05-2012, 04:48 PM
How do I check my cars rpm if I have no gauge on my dash. And what shoukd it be, and what would be some issues if its to high or too low. Also when I change gear from park the cars idle slows and each gear the car jerks hard. U can really feel the car move.
carrfixr
09-05-2012, 04:53 PM
lets start by what year caprice we are talking about
Ajillag
09-05-2012, 05:23 PM
1984 stock 305
carrfixr
09-05-2012, 07:17 PM
How do I check my cars rpm if I have no gauge on my dash. And what shoukd it be, and what would be some issues if its to high or too low. Also when I change gear from park the cars idle slows and each gear the car jerks hard. U can really feel the car move.
you need an external tachometer to read your rpm's. i use an inductive timing light that also displays rpm's.
idle speed spec is 650 in drive.
this info is assuming that your engine management system is intact and functioning properly. if idle is to low can cause roughness and stalling if idle is to high it can cause harsh shifting into drive or reverse, runaway when taking foot off brake etc. you state each gear your car jerks hard upshifting ck the vacuum hose to the transmission vacuum modulator valve. that can cause shifting and idle problems
Set idle with Air-Conditioning unit turned OFF (unless otherwise specified on engine label).
1981-88 Gasoline Engines : Make all adjustments with engine at operating temperature, choke fully open, and electric cooling fan off (if equipped). Engines with idle speed control, idle adjustments are not recommended during tune-up.
Engines with C-4 system, connect dwell meter to carburetor fuel valve lead and ground. Set meter to 6-cylinder scale. When needle begins to vary engine is in closed loop mode and is ready to adjust.
All other engines, disconnect and plug vacuum hoses indicated on emissions label.
Adjust idle solenoid screw, plunger fully extended, or carburetor idle speed screw to specification. If equipped with idle stop solenoid, disconnect the electrical lead and adjust carburetor body screw to specification.
Engines equipped with air-conditioning speed-up solenoid, turn A/C on and disconnect compressor clutch wire. Adjust solenoid to specification with plunger fully extended.
To set fast idle, set choke cam on specified step and adjust engine speed to specification.
you need an external tachometer to read your rpm's. i use an inductive timing light that also displays rpm's.
idle speed spec is 650 in drive.
this info is assuming that your engine management system is intact and functioning properly. if idle is to low can cause roughness and stalling if idle is to high it can cause harsh shifting into drive or reverse, runaway when taking foot off brake etc. you state each gear your car jerks hard upshifting ck the vacuum hose to the transmission vacuum modulator valve. that can cause shifting and idle problems
Set idle with Air-Conditioning unit turned OFF (unless otherwise specified on engine label).
1981-88 Gasoline Engines : Make all adjustments with engine at operating temperature, choke fully open, and electric cooling fan off (if equipped). Engines with idle speed control, idle adjustments are not recommended during tune-up.
Engines with C-4 system, connect dwell meter to carburetor fuel valve lead and ground. Set meter to 6-cylinder scale. When needle begins to vary engine is in closed loop mode and is ready to adjust.
All other engines, disconnect and plug vacuum hoses indicated on emissions label.
Adjust idle solenoid screw, plunger fully extended, or carburetor idle speed screw to specification. If equipped with idle stop solenoid, disconnect the electrical lead and adjust carburetor body screw to specification.
Engines equipped with air-conditioning speed-up solenoid, turn A/C on and disconnect compressor clutch wire. Adjust solenoid to specification with plunger fully extended.
To set fast idle, set choke cam on specified step and adjust engine speed to specification.
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