She's been very temperamental lately!
10-11-13, 03:48 PM
#1
She's been very temperamental lately!
Ok, so I'm still trying to track down this miss or stutter the car is having. It's slowly getting worse. I believe this is the same problem I had even before I did the caps in the ECU, but its much worse and seems to be getting worse every day.
I replaced:
ECU caps (the correct ones)
Coils
cap and rotors
plugs and wires
AFM/MAF
ECT sensor (OEM)
also no vacuum leaks that I know of, but I'll be checking again too
Things I'm going to check in the next few days. I'm going to take a look at the trunk harness again. I've looked at a few weeks back and didn't see any damage, but I'm going to take a bit more time and inspect it again. I'm also going to try and hook up a fuel pressure gauge to the fuel rail and try and position it so I can see it while driving. I want to see if maybe I'm having some pump issues or not.
The car starts up just fine, but under a load hesitates and stubbles as your driving. This morning I was sitting in the drive thru waiting on some food and it was stumbling pretty hard, acting as if it was going to die on me. (never died though)
I'm still currently missing second gear, so first gear revs out a bit more than normal. You really notice it when in first gear when accelerating. The best way I can describe it is that it just falls out. Like a fuel cut on a turbo car or something.
It's less noticeable when your cruising at highway speeds but feels more like its bogging down. You can feel it going in and out as your accelerating.
I know I brought this up before, but I'm still at a loss with this. I've been replacing parts when I can with OEM stuff, but haven't had any luck yet.
Any other ideas? I might try and take a video tonight and I'll post it. When it stumbles the tach needle drops pretty hard. You guys should be able to hear and see it pretty well.
I replaced:
ECU caps (the correct ones)
Coils
cap and rotors
plugs and wires
AFM/MAF
ECT sensor (OEM)
also no vacuum leaks that I know of, but I'll be checking again too
Things I'm going to check in the next few days. I'm going to take a look at the trunk harness again. I've looked at a few weeks back and didn't see any damage, but I'm going to take a bit more time and inspect it again. I'm also going to try and hook up a fuel pressure gauge to the fuel rail and try and position it so I can see it while driving. I want to see if maybe I'm having some pump issues or not.
The car starts up just fine, but under a load hesitates and stubbles as your driving. This morning I was sitting in the drive thru waiting on some food and it was stumbling pretty hard, acting as if it was going to die on me. (never died though)
I'm still currently missing second gear, so first gear revs out a bit more than normal. You really notice it when in first gear when accelerating. The best way I can describe it is that it just falls out. Like a fuel cut on a turbo car or something.
It's less noticeable when your cruising at highway speeds but feels more like its bogging down. You can feel it going in and out as your accelerating.
I know I brought this up before, but I'm still at a loss with this. I've been replacing parts when I can with OEM stuff, but haven't had any luck yet.
Any other ideas? I might try and take a video tonight and I'll post it. When it stumbles the tach needle drops pretty hard. You guys should be able to hear and see it pretty well.
10-11-13, 06:26 PM
#4
Did you check around the serpentine belt? There are wire clips that break and sometimes those wires rub against the belt. They can be hard to notice if you aren't looking for them. Had that happen to me once.
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10-14-13, 04:55 PM
#9
Ok so today I started checking out everything I could on the car. I had it idling as I was moving wires, plugs and everything else I could get my hands on. Didn't find anything that made a difference.......... Until I shut the hood. When the hood shut, the car stumbled from the vibration! I couldn't believe it. I did it a few more times and same thing. So I got a screw driver and started tapping on things with the engine running. Came down to the AFM/MAF. Every time I tapped anywhere near the AFM the car stumbles and it even died once. Now, I've replaced the AFM before and have tried two different ones, but that was also before I did the ecu caps. So I went and took the AFM off of my SC and hooked it up. And started to tap around that area again with it running. It did NOT stumble this time! I ran out of time this morning (had to go to work), but I'll take it for a test drive in the morning.
I'm really hoping this was my issue. I mean it diffidently makes sense. I'll let you guys know tomorrow for sure!
I'm really hoping this was my issue. I mean it diffidently makes sense. I'll let you guys know tomorrow for sure!
10-14-13, 05:25 PM
#10
Lexus Champion
many AFM's (94 and earlier) are bad due to someone having cleaned them with solvent during their life, so someone might sell you one that is "tested good" but I would be very suspicious of any AFM that is not brand new!
also the temp sensor portion of these 94 and earlier AFM's goes bad all of the time!
also the temp sensor portion of these 94 and earlier AFM's goes bad all of the time!
10-14-13, 07:09 PM
#11
Yeah, I've come to that conclusion too. I bought one off the forum for $50 and it is the one that I just took out of the car. I had also bought one for $60 at the local junk yard and tried it. I ended up returning it. They would only give me a yard credit so I used it to get my 95+ brake calipers for $50 and still had some left over for some other parts. 
Like I said I'll take this thing for a spin first thing tomorrow and see how she drives. The only downside is that if this fixed it, now I have to find another good one for my SC!
Like I said I'll take this thing for a spin first thing tomorrow and see how she drives. The only downside is that if this fixed it, now I have to find another good one for my SC!
10-14-13, 08:57 PM
#12
Ok, so I couldnt wait until tomorrow. I took the car out for a drive tonight when I got home. It seems to be running pretty darn good, I was playing with the TPS and I'm pretty sure its out of adjustment because she was a little slower than normal off the line. But it looks like the 4th-5th(not sure) AFM might have fixed it. 
Now I just need to pull the pan off the trans and have a look at everything. I'm still missing that second gear.
After I fix the trans, I think she will be fun to drive again.
Now I just need to pull the pan off the trans and have a look at everything. I'm still missing that second gear.
After I fix the trans, I think she will be fun to drive again.
10-15-13, 01:58 AM
#13
Lexus Champion
check all three of your throttle cables near TPS (main, transmission, cruise)
all should be almost taunt, but with a little slop in each one - just enough slop to feel and see with finger, but not taunt (not tight) - but not gobs of play either
so like main throttle cable start moving ever so slightly before TPS does
also follow main TPS adjustment in the service manual on page EG-589
all should be almost taunt, but with a little slop in each one - just enough slop to feel and see with finger, but not taunt (not tight) - but not gobs of play either
so like main throttle cable start moving ever so slightly before TPS does
also follow main TPS adjustment in the service manual on page EG-589
Last edited by LScowboyLS; 10-15-13 at 02:04 AM.
10-15-13, 06:33 AM
#14
Pole Position
Glad to hear it's running better again. But you still need to find a good AFM to put back on your SC, unless you keep changing it back and forth. 
Speaking of TPS; (I'm a procrastinator) I've had a good TPS in my center console for 2 years now just never installed it.
Sometimes I'm an idiot. But it only hesitates a tiny bit at 42 and 62 MPH. So I don't drive at those speeds.
One of these days.
Hope you get that 2nd gear fixed, it must be a PITA without it.
Speaking of TPS; (I'm a procrastinator) I've had a good TPS in my center console for 2 years now just never installed it.
Sometimes I'm an idiot. But it only hesitates a tiny bit at 42 and 62 MPH. So I don't drive at those speeds. One of these days. Hope you get that 2nd gear fixed, it must be a PITA without it.
10-15-13, 06:55 AM
#15
Lexus Champion