Engine Stalls At Idle - After Warm-Up - Mazda MX-5 1990 Workshop Manual

I
I
TROUBLESHOOTING GUIDE
STEP INSPECTION
5 Check if air cleaner element is clean
c:::r page F-75
6 Disconnect ISC valve connector when engine is
cold and note idle speed
Check if engine speed decreases after warm-up
7 Try known good ECU and check if condition
Improves
ACTION
Yes Go to next step
No Replace air cleaner element
Yes Go to next step
No Check air valve
Yes Replace ECU
c:r page F-127 No Change fuel to another brand
17 ENGINE STALLS AT IDLE - AFTER WARM-UP
DESCRIP·
TION
• Engine runs normally at idle during warm-up but becomes rough and stalls after warm-up
[TROUBLESHOOTING HINTS]
CD
Air/Fuel mixture too lean
- Air leakage of intake air system
STEP
INSPECTION
Check if air is leaked from intake air system
component
c:::::r
page
F-93
2 Disconnect ISC valve connector at idle and
check if "clicking" is heard from ISC Valve
3 Go to troubleshooting No.10 "LOW IDLE
SPEED/ROUGH IDLE-AFTER WARM-UP"
c:::::r
page F-34
@ Low intake air amount
-Idle speed control malfunction
ACTION
Yes Repair or replace
No Go to next step
Yes Go to next step
No Replace ISC valve
F
c:r
page
F-92
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page
F-99
[.J
page F-127
05UOFX-033
c:r
page
F-93
c:::r page F-99
05UOFX-034
F-45