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Renix era issues

Old 02-12-2018, 07:41 AM
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Originally Posted by Oswalla
I would have to agree, it is more common than a rich condition. Wonder how his temps are ? Lean can heat up the motor.

Satirical Hen, hows that exhaust look I mentioned earlier ? Rich condition will generally be excess black smoke when revved. Another rich sign is easy to check those plugs, if they look good and dry follow the lean condition. Get an extension hose for that pressure tester and run it up to windshield and drive it like Cruiser suggested.
No black smoke, when warmed up bluish smoke seems to produce the most when idling at lights and such (oil level hasn't noticeably changed in 1500 miles), runs just under 210 all the time. I would upload pictures of the plugs, but for some reason I haven't been able to upload pictures to the site.
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Old 02-12-2018, 07:43 AM
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Have you checked the tightness of the intake manifold nuts?

sprayed carb cleaner at suspected vacuum leaks with the engine running?
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Old 02-12-2018, 08:12 AM
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Originally Posted by cruiser54
Have you checked the tightness of the intake manifold nuts?

sprayed carb cleaner at suspected vacuum leaks with the engine running?
I haven't gone and tightened the intake bolts, but there doesn't seem to be any vacuum leaks. Idles right at 750 and I haven't been able to locate any leaks. I disconnected the heater valve, but plugged the vacuum line to it. Don't know if it makes a difference, but when I'm on the brakes it idles up and I can hear an air sound and when I let off idle will drop for a second then pick back up.
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Old 02-12-2018, 08:14 AM
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Originally Posted by SatiricalHen View Post
I haven't gone and tightened the intake bolts, but there doesn't seem to be any vacuum leaks. Idles right at 750 and I haven't been able to locate any leaks. I disconnected the heater valve, but plugged the vacuum line to it. Don't know if it makes a difference, but when I'm on the brakes it idles up and I can hear an air sound and when I let off idle will drop for a second then pick back up.
Sounds like your booster is bad. Disconnect the hose from the booster and plug it. See how that affects the idle quality.
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Old 02-13-2018, 04:58 PM
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Checked vacuum at the map and definitely has vacuum
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Old 02-13-2018, 08:38 PM
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Originally Posted by SatiricalHen View Post
Checked vacuum at the map and definitely has vacuum
But it will be low vacuum if your booster is leaking internally. The low vacuum will tell the MAP sensor the engine needs more fuel.
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Old 02-13-2018, 09:35 PM
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Originally Posted by cruiser54
But it will be low vacuum if your booster is leaking internally. The low vacuum will tell the MAP sensor the engine needs more fuel.
Do you suggest I remove the vacuum line from the booster and drive it plugged to see if it runs better? It only backfires and stumbles when driving. I can't get it to when running with no load. The brakes don't do much at all without the booster hooked up, and I'm not sure id even be able to stop it
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Old 02-13-2018, 09:38 PM
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Originally Posted by SatiricalHen View Post
Do you suggest I remove the vacuum line from the booster and drive it plugged to see if it runs better? It only backfires and stumbles when driving. I can't get it to when running with no load. The brakes don't do much at all without the booster hooked up, and I'm not sure id even be able to stop it
Yes. don't drive in heavy traffic.
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Old 02-13-2018, 09:56 PM
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Originally Posted by cruiser54
Yes. don't drive in heavy traffic.
It may have improved it slightly, but it still did stumble and backfire. It didn't seem as violent and harsh as before though.
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Old 02-14-2018, 07:12 AM
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Originally Posted by SatiricalHen View Post
It may have improved it slightly, but it still did stumble and backfire. It didn't seem as violent and harsh as before though.
So, you may have more than one issue contributing to the problem......
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Old 02-14-2018, 11:40 AM
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Originally Posted by cruiser54
So, you may have more than one issue contributing to the problem......
My roommate has a theory about my issues. The front edge of the exhaust manifold is pulling away from the head, by about 1/8" and he thinks it could be creating a gap in the intake since they share the same bolts/studs for mounting. Do you know what the vacuum readings should be? I could rent or buy a vacuum tester and see what it's reading. That would tell me if I had more leaks or anything.
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Old 02-14-2018, 01:00 PM
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Also, I looked at another thread with driving issues and they had a bad egr valve causing a large vacuum leak basically. Might look into that some.
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Old 02-14-2018, 01:01 PM
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Originally Posted by SatiricalHen View Post
I haven't gone and tightened the intake bolts, but there doesn't seem to be any vacuum leaks. Idles right at 750 and I haven't been able to locate any leaks. I disconnected the heater valve, but plugged the vacuum line to it. Don't know if it makes a difference, but when I'm on the brakes it idles up and I can hear an air sound and when I let off idle will drop for a second then pick back up.
Check bolts anyway when up to operating temp. Just good measure..
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Old 02-14-2018, 01:02 PM
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Originally Posted by SatiricalHen View Post
Also, I looked at another thread with driving issues and they had a bad egr valve causing a large vacuum leak basically. Might look into that some.
Could be sticking very possible.
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Old 02-14-2018, 04:16 PM
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Use carb cleaner and spray it in areas you suspect a leak, with the engine running at idle.
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