89 L98 hard start when engine is cold
#1
Heel & Toe
Thread Starter
89 L98 hard start when engine is cold
Recently my '89 convertible starts hard when it is cold. It starts fine when warmed up. Could you point me to possible causes? I put in platinum plugs about 10,000 miles ago along with Bosch plug wires. Fuel pump and filter were replaced 12,000 miles ago. Any advice would be greatly appreciated.
#3
Heel & Toe
Thread Starter
'89 L98 hard start when engine is cold
Thanks for your reply. It takes about 60 to 90 seconds to start. It has always started immediately in the past. The odometer reads 69,583 miles.
#4
Instructor
60 to 90 seconds is harsh. that will burn a starter up after a while.
how old are the injectors? if it were oil pressure it would take about 10 seconds or less to hit the pressure switch. eliminate that.
fuel pressure regulator? put a fuel pressure guage on it to see if the pressure comes right up and holds in the 36 to 44 pound range
how old are the injectors? if it were oil pressure it would take about 10 seconds or less to hit the pressure switch. eliminate that.
fuel pressure regulator? put a fuel pressure guage on it to see if the pressure comes right up and holds in the 36 to 44 pound range
#5
Heel & Toe
Thread Starter
I'll check the fuel pressure. The injectors were replaced 5 years ago. I don't crank the starter for 60-90 seconds at a time but in 15 second increments as specified in the owner's manual. (I'm sure that's still not good for the starter) Thanks for your advise.
#6
Burning Brakes
Two possibles - I think 89s have a cold start injector? Somebody help here - my 89 manual is on loan. Also, the ECM sees the engine temperature and the sensor may have failed making the ECM think the engine is hot when it really isn't. I think there are two coolant sensors in the 89, one for the gauge and the other for the ECM input. Check the ECM one with a tech 1 or some other scan tool.
#7
Burning Brakes
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Like previously stated could be a bad coolant temp sensor(for ECM) or intake air temp sensor(if it has one).Could also be a leaky fuel pressure regulator.Let us know what you find
#8
Drifting
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St. Jude Donor '10
I have an 87 which does have the cold start injector. I have been told by others on the forum that the 89 doesn't. This issue came up as I was planning to change the ecm to run on the 89 bin which is reportedly a better code than the 87 and which doesn't use an extra injector for cold starts.