I verified the WOT switch works with a meter (0 resistance when open) and I changed the 02 sensor out last week with a new one from D goOriginally Posted by Bitsyncmaster
Location: Danvers, ma
Posts: 104
My VIN: 4328
I verified the WOT switch works with a meter (0 resistance when open) and I changed the 02 sensor out last week with a new one from D go
Location: Danvers, ma
Posts: 104
My VIN: 4328
I put a new connector on the frequency valve and verified power at the plug, lambda ecu and idle ecu both have power
Posts: 743
What is the dwell reading? It defaults to specific values depending on what’s happening. The frequency valve not buzzing can happen when the mixture is way off.
Location: Danvers, ma
Posts: 104
My VIN: 4328
I got new plugs and wires on this afternoon. That cleared up the hesitation I was getting. Has more power at low rpms than ever before! I ran out of daylight and therefore didn't get the dwell never on but I turned the co screw more lean by a 1/4 turn to cut out the rich exhaust smell. Still no buzz from the frequency valve so ill have to do a bit more investigating this weekend. The plugs were AC Delco with the #16 on them
Posts: 4,764
My VIN: Banged your VIN'S mom
1/4 turn is a BIG adjustment! Messing with that mixture without a meter is asking for trouble. The new plugs may buy you some time till you foul them out again. Get yourself a dwell meter but until then you can use a multi meter which you probably already have laying around.
Location: Northern NJ
Posts: 8,576
My VIN: 10757 1st place Concourse 1998
If you are not getting not "closed loop" and the frequency valve is not buzzing and you were running over-rich, the O2 sensor is probably fouled. Replace it and see if that gets you into closed loop. By getting a dwell meter on and getting a reading, any reading, it tells you that at least the Lambda control is alive and working a little. As Michael said, 1/4 turn is a huge amount. If you were that far off your catalytic converter and muffler was probably glowing red, besides the overwhelming smell. Without a dwell meter the only adjustment you should attempt to the mixture screw is to set it so that you just shut off the fuel injectors. That only gets you close, about a 1/8 turn away from optimum, close enough for the motor to run without fouling out the plugs, O2 senor or converter. If the tamper proof plug is still in the mixture unit you should not touch the mixture screw. If the mixture screw hasn't been molested it is probably as close to perfect as you would get it trying to adjust it with a dwell meter. Not in your case if you already twisted it 1/4 turn. Do NOT adjust the mixture screw unless the fuel injectors are all spraying good patterns and equal amounts, there are NO vacuum leaks and everything is set perfectly. You CANNOT adjust away a problem with the mixture screw.
David Teitelbaum
Location: Danvers, ma
Posts: 104
My VIN: 4328
The mixture was messed with long before I got it. I am trying to fix what was done to it prior to get it running better. It has always run and started no problem, I drove it home 1400 miles before it had any tune up at all after 27 years sitting. It had all new fuel lines and fuel distributor and filter and such done, i just did the plugs and wires and o2 sensor and relays and fuses within the past week or 2. Whoever worked on it prior adjusted it to just get and keep it going. Now that I did the tune up I am leaning out the mixture and will put a dwell meter on it today to further correct it. I will post my dwell readings later this afternoon to see if I am going in the right direction with all of your help i hope!
Posts: 159
Looks like you are on the right track but don’t do too much messing with the mixture screw without a dwell meter. As others I’ve said 1/4 of a turn and you can be well past limits and all that happens is that you end up chasing your tail and fouling plugs along the way. Post the dwell readings when you can but don’t touch the mixture screw anymore until you do. Also make sure there are no vacuum leaks at all before tampering with mixture. Get a smoke test done if you can. Also how old are your injectors? Could be good to get them tested for peace of mind.
Location: Richmond Va.
Posts: 142
Recently started in the heat of the south. 20069 idles high but smooth. Very slight pedal car will speed up ok exceed that very small pedal car bogs down hesitates until you floor it and hit the wot switch. This is in all
gears. Today temp. 75* started out drive as above. Fueled car all well on drive home.
Open for suggestions
Steve
Location: Leonardtown, MD
Posts: 9,003
My VIN: 03572
Those symptoms tell me your mixture is lean.
Posting Permissions
Reply With Quote
Dave M vin 03572