Won't run right!
04-20-2015, 08:15 AM
#1
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Join Date: Mar 2015
Posts: 30
Won't run right!
I just put a new engine in my 88 z31 it has run great until today when I started it and it is running rough. It's like it's not firing all 6 cylinders. When it's running it has white smoke from the tail pipe and the exaust smells like gas. It was running great yesterday and had no exaust smoke either. Could it not be getting spark? I am kinna stumped so any help is appreciated.
04-20-2015, 10:21 AM
#3
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Tried all of that stuff. The ecu gave code #23 the plugs are good. My only concern is the fuel I feel like the pressure is down but I'm going to get a gauge to see what it atcualy is. It runs great if you let the fuel pump cut off and then fire it up but after about 10 seconds it starts to run rough
04-20-2015, 10:59 AM
#4
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Join Date: Aug 2013
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Code 23 sends you to the throttle valve switch and circuits. Did you check out your switch operation and the throttle position sensor? They have to work right. Check your manual at page EF&EC 63. Also check for loose/dirty/corroded harness connectors and clean them.
Last edited by zxguy1986; 04-20-2015 at 11:11 AM.
04-20-2015, 06:48 PM
#7
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Okey so here's an update. I checked and all cylinders are getting spark and the ECU is no longer reading any problems. I'm thinking it might be a fuel issue. When you first start the car it fires up fine and then runs for about 3 seconds before it runs rough. Maybe it's not getting enough pressure? I am trying to get ahold of a pressure gauge so I can check.
04-21-2015, 03:21 PM
#10
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Join Date: Sep 2006
Location: Mill Creek WA
Posts: 1,415
could be the chts. could be O2 sensor. there were different sensors used on different years. easy way to check unplug O2 sensor and drive around until everything warm. if no die you know the answer. if no change time for a chts. be sure the egr isn't stuck open. stick a finger up there and see if the diaphragm gives and returns.
04-22-2015, 05:18 AM
#11
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Update
Okay so I changed the chts and got a new catalytic converter because a friend of mine had had the same problem and it had been the cat. I also tried unplugging the O2 sensor and running it but it didn't help. I'm going to check the erg valve today.
04-24-2015, 10:17 AM
#14
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Join Date: Sep 2006
Location: Mill Creek WA
Posts: 1,415
codes fairly useless at the age of everything. it isn't an afs those are on s130. you have a MAF there is a diagnostic procedure in the FSM. you need a VOM and some jumpers. Have you checked your fuel pressure? Have you checked the vacuum at idle? If you are still getting white smoke you got a blown head gasket.
