Rough running after water pump change..
09-17-2018, 05:33 PM
#1
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Location: Northeast Ohio
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Rough running after water pump change..
Hey guys I need help.
95 camaro z28
373 gears 3600 yank full exhaust and slp intake.
I changed the water pump, temp sensor, and coolant sensor. When i started the car there no was engine light but it is idling around 800. When I drive it it cruises well but accelerating has a miss. Obviously the air pump was apart and spark plug wires were removed. I cleaned the throttle body, maf sensor, and made sure everything was dry. Do you guys have any idea what happened? Would a bad wire not throw a CEL?
95 camaro z28
373 gears 3600 yank full exhaust and slp intake.
I changed the water pump, temp sensor, and coolant sensor. When i started the car there no was engine light but it is idling around 800. When I drive it it cruises well but accelerating has a miss. Obviously the air pump was apart and spark plug wires were removed. I cleaned the throttle body, maf sensor, and made sure everything was dry. Do you guys have any idea what happened? Would a bad wire not throw a CEL?
Last edited by Mc1995z28; 09-17-2018 at 05:35 PM. Reason: Left out mods
09-17-2018, 07:19 PM
#2
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Location: Hell was full so they sent me to NJ
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Re: Rough running after water pump change..
Did you spill coolant on the distributor?
There is no misfire detection in OBD-1, so no check engine light/code for a faulty plug wire.
What is the programmed idle speed? Are you reading the RPM from the factory tach (not necessarily accurate) or the PCM via a scanner? Is the 800 RPM with the coolant fully warmed up?
There is no misfire detection in OBD-1, so no check engine light/code for a faulty plug wire.
What is the programmed idle speed? Are you reading the RPM from the factory tach (not necessarily accurate) or the PCM via a scanner? Is the 800 RPM with the coolant fully warmed up?
09-17-2018, 07:49 PM
#3
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Join Date: Sep 2018
Location: Northeast Ohio
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Re: Rough running after water pump change..
Yes the car has the obd2 styled obd1. I have the cable and have detected faulty oxygen sensors in the past but not spark plug wires. It was a little wet but I kept it covered. Stock rpm 650 I believe going off of my tachometer. You can also slighty hear something missing in the exhaust note.
09-18-2018, 09:16 AM
#4
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Location: Hell was full so they sent me to NJ
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Re: Rough running after water pump change..
Just to be clear, the only OBD-2 (style) component on a 95 is the 16-pin DLC under the dash. The PCM is totally identical to the OBD-1 1994. Without the crank position sensor, added in 1996 with implementation of OBD-2, there is no misfire detection. There is no way to directly measure a fault in the high voltage side of the ignition.
Check the plug and coil wire ends and sockets at the Opti for moisture or corrosion. Pull the Opti harness connector and look for corrosion.
Also check the Connection on the coolant temp sensor on the water pump. A loose connection or corrosion can increase resistance, and high resistance = low temperature input to the PCM. The PCM richens the A/F ratio and elevates idle RPM with low temp.
Since you have “the cable” what scanner are you using? Does it have data logging capability? Have you considered Scan9495?
https://www.camaroz28.com/forums/com...95-lt1-874306/
Check the plug and coil wire ends and sockets at the Opti for moisture or corrosion. Pull the Opti harness connector and look for corrosion.
Also check the Connection on the coolant temp sensor on the water pump. A loose connection or corrosion can increase resistance, and high resistance = low temperature input to the PCM. The PCM richens the A/F ratio and elevates idle RPM with low temp.
Since you have “the cable” what scanner are you using? Does it have data logging capability? Have you considered Scan9495?
https://www.camaroz28.com/forums/com...95-lt1-874306/
Last edited by Injuneer; 09-18-2018 at 09:21 AM.
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