Troubleshooting Guide — 17 Hesitates/Stumbles on Acceleration
F2-48flowchart17 HESITATES/STUMBLES ON ACCELERATION
DESCRIPTION: Flat spot occurs just after accelerator is depressed, of mild jerking occurs during acceleration
NOTE
[TROUBLESHOOTING HINTS]
1. Air/fuel mixture becomes lean when depressing accelerator
• Fuel injection control malfunction (Correction for accelerating condition)
• Air leakage
• Fuel line pressure decreases
• Spark advance control malfunction
17 Hesitates/Stumbles on Acceleration
1
STEP 1: Is "00" displayed on SST with ignition switch ON? (page F2-73)
No
Diagnostic trouble code No. displayed — Check for cause (Refer to specified check sequence) (page F2-74)
Yes
2
"00" displayed — Go to next step
3
STEP 2: Is intake manifold vacuum correct at idle? Vacuum: More than 450 mmHg {17.7 inHg}
No
Check for air leakage of intake-air system components
Yes
4
Go to next step
5
STEP 3: Is air cleaner element clean? (page F2-70)
No
Replace air cleaner element
Yes
6
Go to next step
7
STEP 4: Are ECM terminal voltages OK (especially 2F, 2I)? (page F2-141)
No
Check for cause
Yes
8
Go to next step (page F2-141)
9
STEP 5: Is throttle linkage correctly installed and does it operate freely?
No
As required, correct, clean, or replace any binding or damaged linkage, and adjust cable deflection at throttle body
Yes
10
Go to next step
11
STEP 6: Check for continuity between throttle position sensor terminals C and D (page F2-150). Clearance between throttle lever and stopper 0.15 mm {0.006 in} → Continuity Yes; 0.50 mm {0.020 in} → Continuity No
No
Adjust throttle position sensor (page F2-151)
Yes
12
Go to next step
STEP 6 — Throttle position sensor continuity
0.15 mm {0.006 in}
ContinuityYes
0.50 mm {0.020 in}
ContinuityNo