87 runs rough...help please
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Joined: Dec 1999
Posts: 98
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From: Graniteville SC
87 runs rough...help please
Car idles smoothly. The car runs fine until it reaches running temp (160....hypertech chip and thermostat) it cuts out upon acceleration but when I get off the gas it smoothes out. I thought it was water in the fuel but I visually inspected the fuel and added an additive and found no water. I checked the filter no water.
I recieved a code 33 today after replacing the fuel filter? Wierd?
Has anyone experienced simular problems?
All help is appreciated,
Larry
I recieved a code 33 today after replacing the fuel filter? Wierd?
Has anyone experienced simular problems?
All help is appreciated,
Larry
Drifting
Joined: Mar 2001
Posts: 1,636
Likes: 3
From: Lafayette IN
Re: 87 runs rough...help please (87redvette)
I would do a tap test on the MAF sensor. With the handle of a screwdriver, once the engine is up to temp and in park, lightly tap the handle on the housing of the sensor with the same amount of force you would use to crack an egg without it splattering anywhere. Note any sputtering or RPM flux.
If it runs erradically, this could be your problem. It is possible that your MAF was sending some wrong singals to the ECM and with a dirty fuel filter, the engine was normally lean. Now that you replaced the FF, it is rich and the engine is seeing the wrong air entering.
You might also want to do a search under MAF burnoff and MAF power relays. -Matt-
[Modified by HighHopes85, 1:21 PM 12/15/2001]
If it runs erradically, this could be your problem. It is possible that your MAF was sending some wrong singals to the ECM and with a dirty fuel filter, the engine was normally lean. Now that you replaced the FF, it is rich and the engine is seeing the wrong air entering.
You might also want to do a search under MAF burnoff and MAF power relays. -Matt-
[Modified by HighHopes85, 1:21 PM 12/15/2001]
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Re: 87 runs rough...help please (HighHopes85)
code 33 is the MAF which is just behind your air filter housing. Replace the two relays on the firewall first, if that doesnt work replace the MAF (go ahead and take out the screens before you put it in).
If that doesnt fix your roughness, replace plugs. wires, distributor and rotor.
If that doesnt fix your roughness, replace plugs. wires, distributor and rotor.
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Joined: Mar 2001
Posts: 74
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From: Brooklyn NY
Re: 87 runs rough...help please (87redvette)
I had a similar problem with my 87' L98 recently. I had a loose spark plug wire which I tightened and solved my problem. I hope your solution is as simple as mine to fix. Good luck!
