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Interesting ride home. What happened?

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KLUTZ

KLUTZ

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I got my gas tank down as low as I thought was safe, and put in Sunoco 94 octane, instead of the regular 87 octane that I had used, as my mechanic requested I do. He said it would be a nice present, and help get the idle down from 1500.
Anyway, the TR7 has driven beautifully for a couple weeks with the regular, including on the way to work this morning. After work, I filled up with the 94, and hit the hiway. Crusing with trafic at around 120 KPH, I didn't notice a diference. After about 50 KM, the car started loosing power, and running funny. I had to pull off of the hiway, to the shoulder. I got out, and the engine sounded like the timing was off all of the sudden, and really rough, but running. I managed to slowly drive another Kilometre and get to a school parking lot off the hiway.
I shut the car off, and started it again after about 3 minutes. There was no sign of any problems after that. The rest of the 30 KM was great. Lots of pick up, lots of power, idle around 1200 now.
What happened there???

Thanks
Paul
confused.gif
 
Hmmmm. I don't think extra octane did anything for or to the car. Octane has zero to do with idling at 1500 RPM. That has to do with a misadjusted carb, and mostly likely a stuck deceleration bypass valve. Haynes has a section on this.

Symptom this? Start up and when things are first warmed up the idle is fine even with the choke off. But after a long run, the thing just won't slow down? You can kick the accelerator a few times and sometime it will help but usually not.

If so, check Haynes page 46 sections 10.23-31. See also page 47, Fig 3.12 lower left corner of the page.

As to what did happen -- Maybe some gunge dredged up by letting the tank run right down. Fuel starvation from a clogged filter? Vapor lock? Maybe though it wouldn't clear in 3 minutes. If you have original electronic ignition, it can get hot. Running rough sounds electrical in this case.

By rough you mean? Missing? Worse when you give it gas? Would it idle then or did it die?
 
<blockquote><font size="1" face="Verdana, Arial">quote:</font><hr>Originally posted by MichaelF:

Symptom this? Start up and when things are first warmed up the idle is fine even with the choke off. But after a long run, the thing just won't slow down? You can kick the accelerator a few times and sometime it will help but usually not.

If so, check Haynes page 46 sections 10.23-31. See also page 47, Fig 3.12 lower left corner of the page.

If you have original electronic ignition, it can get hot. Running rough sounds electrical in this case.

By rough you mean? Missing? Worse when you give it gas? Would it idle then or did it die?<hr></blockquote>

Yes, rough when giving gas, idled fine otherwise. Had to barly touch the gas to get off the hiway.
I put in a new starter relay a couple days ago because the car would just click after a long run, and had to be push started.
That got rid of that problem. It has the origional ignition still.
Thanks
 
<blockquote><font size="1" face="Verdana, Arial">quote:</font><hr> After about 50 KM, the car started loosing power, and running funny. I had to pull off of the hiway, to the shoulder. I got out, and the engine sounded like the timing was off all of the sudden, and really rough, but running. <hr></blockquote>

What ignition system does it have, the Delco one? What you're describing sounds like what my car did last year when the coil went out. After about 1/2 hour of high speed driving, the car would cough, sputter, and feel like it was starved for gas. It would usually die. In fact, it was starved for spark, as when the coil got hot it was shorting out internally. Shut the car off (if it didn't die) and let it sit for a few minutes, and it would start up and drive again fine...maybe for a few miles, maybe the rest of the day. Have a tester handy, and when (if) it happens again, see if the coil's putting out juice.
 
<blockquote><font size="1" face="Verdana, Arial">quote:</font><hr>Originally posted by MichaelF:
Hmmmm. Octane has zero to do with idling at 1500 RPM. <hr></blockquote>

grin.gif
grin.gif


Sorry, I didn't mean to imply that he said the extra octane would lower the idle... Just that it would clean things up better for when I bring it in for adjustment.
smile.gif
 
<blockquote><font size="1" face="Verdana, Arial">quote:</font><hr>Originally posted by ObiRichKanobi:


it was starved for spark, as when the coil got hot it was shorting out internally. Shut the car off (if it didn't die) and let it sit for a few minutes, and it would start up and drive again fine...maybe for a few miles, maybe the rest of the day. .<hr></blockquote>

Had the exact same problem with 2 brand new Lucas coils. Now I use a cheapo NAPA coil and have not had a problem.
 
I have a couple extra coils here. Will play around today. But, if I fix that, what will be next? /ubbthreads/images/graemlins/smirk.gif
 
[ QUOTE ]
I have a couple extra coils here. Will play around today. But, if I fix that, what will be next?

[/ QUOTE ]

Ah yes, the charm of LBCs /ubbthreads/images/graemlins/grin.gif
 
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