Help !!!! strange surge right after startup
Thread Starter
Burning Brakes
Joined: Apr 2001
Posts: 992
Likes: 0
From: Atlanta GA
Help !!!! strange surge right after startup
Car was running great..... then all of a sudden this week about 2 days ago I started it and right away it almost stalled out then came right back to life.... It did again after a few more minutes and then was fine... It drove fine all the way home....Next morning did the same thing ....Today the same thing..... I checked codes and found a 33 and 42....I think the 42 is there from the last time I checked timing.... I cleared them and it still wants to do the same thing...Like I said it does not affect driving, or at least it does not feel like it.....
It anybody can help with this one.....Please do...I am at a loss.... I have checked for loose conections or hoses or anything out of the norm...But don't see anything....
Thanks in advance....
It anybody can help with this one.....Please do...I am at a loss.... I have checked for loose conections or hoses or anything out of the norm...But don't see anything....
Thanks in advance....
Team Owner
Joined: Mar 2001
Posts: 54,124
Likes: 30
From: Cincinnati, Oh USA
Re: Help !!!! strange surge right after startup (apollo30346)
Code 33 indicates the ECM has seen flow in excess of 45 gms/sec for one second when: starting, or TPS is less than 1/4 throttle, or rpm is less than 2000. This can happen if circuit 998 (green wire on MAF sensor) is open. Circuit 998 voltage is directly proportional to air flow. Low air flow, low voltage, high air flow, 5 volts at maximum air flow. When you start the engine , the air flow and the voltage on 998 should remain low. There is a whole page on resolving a code 33 and someone may be able to post it. I don't have that capability.
Pro
Joined: Jun 2001
Posts: 509
Likes: 5
From: Edmonds WA
Re: Help !!!! strange surge right after startup (apollo30346)
It means that you may be having trouble with your MAF sensor. You might search archive posts for "MAF" and see what you find. Consider unplugging the MAF and then trying to start the car. If it behaves more normal, it could be the MAF sensor isn't working right. But, you might want to make sure... it's a fairly expensive part.
Thread Starter
Burning Brakes
Joined: Apr 2001
Posts: 992
Likes: 0
From: Atlanta GA
Re: Help !!!! strange surge right after startup (K87ZZ4)
OK,
car is still doing this on initial startup and a little bit after.... It does not efect driving in any way..... But there is something wrong....
Lets say I have no codes thrown.... What would be the cause of this on my car....It died 4 times this morning..... before I ever pulled out of the garage... I was just sitting there as I like to let it run for a minute before turning the A/C on....
I really need help with this...I am scared this is going to leave me straned on the road somewhere....
Please keep the ideas coming.....
car is still doing this on initial startup and a little bit after.... It does not efect driving in any way..... But there is something wrong....
Lets say I have no codes thrown.... What would be the cause of this on my car....It died 4 times this morning..... before I ever pulled out of the garage... I was just sitting there as I like to let it run for a minute before turning the A/C on....
I really need help with this...I am scared this is going to leave me straned on the road somewhere....
Please keep the ideas coming.....
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Thread Starter
Burning Brakes
Joined: Apr 2001
Posts: 992
Likes: 0
From: Atlanta GA
Re: Help !!!! strange surge right after startup (merrick)
ECM and MAF are less than a year old..... I have checked all the conections.....Would a fuel pump relay that is going bad make it reack like this....?
Team Owner
Joined: Mar 2001
Posts: 54,124
Likes: 30
From: Cincinnati, Oh USA
Re: Help !!!! strange surge right after startup (apollo30346)
The fuel pump relay won't set a code 33 which is a very important clue here. It doesn't matter how old your brand new MAF is, it can still fail. About every 1 1/2 yrs when I first got my 87, I had to replace the MAF sensor. For some reason, I haven't had one fail for years now.
You need to follow the diagnosis flow in the repair manual for code 33.
You need to follow the diagnosis flow in the repair manual for code 33.
Pro
Joined: Sep 2001
Posts: 743
Likes: 4
From: Guyton GA
Re: Help !!!! strange surge right after startup (apollo30346)
You should hear your fuel pump come on just as you turn the ignition switch to "on" position. It will turn off when the pressure builds up (2 seconds). If it does this your relay is ok.
....If your car does not run with the MAF elec connector disconected and runs with it connected, then there is a problem with it.
....If your car does not run with the MAF elec connector disconected and runs with it connected, then there is a problem with it.
Thread Starter
Burning Brakes
Joined: Apr 2001
Posts: 992
Likes: 0
From: Atlanta GA
Re: Help !!!! strange surge right after startup (merrick)
I found out what it was.... I feel stupid.... :yesnod: I decided to go out and get some fuel one night and of corse the car did it's little thing of stalling upon startup..... I decided to take a look under the hood again to see if maybe I had a plug wire arching or something.... I looked and did not see anything.... I then got the trusty Mag lite and what did I find..... :cry ...When I put the new H-Balancer on I must have not put the MAF wire harness out of the way of the water pump pulley.... I found that the harness had been rubbing and was ate through .... and one of the wire's was cut all but one tiny strande of wire left that was conected.... I pulled it all apart and fixed and then wrapped it and then put new plastic casing around it and made a nice factory harness and then connected it and wire tied correctly... Car runs normal now.... Like I said I feel stupid....
Thanks for all the help on this.....
Thanks for all the help on this.....
Burning Brakes
Joined: Mar 1999
Posts: 858
Likes: 5
From: Fl,USA
Re: Help !!!! strange surge right after startup (merrick)
What is bad if the car runs with the maf plugged in but stalls with it unplugged and wont restart until its plugged back in? MAF or relay?