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#1 |
![]() Join Date: Jan 2021
Location: Beautiful Bavaria
Posts: 523
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So far my Z runs and idles as silk. But there is some heavy stumbling / hesitation during the transition from idle up into higher revs.
I can feel it slightly when I just rev her up. But with a gear engaged the effect is pretty strong. Let's say I let her crawl in first gear idle and then push the throttle (no matter if carefully or flooring it) the transition out of idle has no power and the beast stumbles. North of 1000 revs she runs great, idle is smooth as well. Any ideas?
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ZR-1 #638/1991 |
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#2 |
![]() Join Date: Jul 2015
Location: Jerica - SPAIN
Posts: 281
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Hi Matt, with my car in last 2015 I had similar symptoms. My problem was with two coils with intermitent failure and two spark wires... I don't know if this can help you...
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#3 |
Join Date: May 2007
Location: Chicagoland, IL
Posts: 9,696
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You should check TPS for dead spot.
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[SIGPIC][/SIGPIC]Former Membership Chairman Former ZR-1 Registry - BOD 1972 Corvette 4speed base Coupe SOLD long time ago 1984 Corvette Z-51/4+3 SOLD 1992 Corvette ZR-1 Aqua/Gray #474 SOLD 1992 Corvette ZR-1 Black Rose/Cognac #458 2014 Honda VFR Interceptor DX |
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#4 |
![]() Join Date: Jul 2004
Location: Kalamazoo MI
Posts: 1,764
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How much has this car been driven and has it seen 7K rpm shifts lately
Might need a Italian tune up
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JOHNNY P Currently own 90 ZR-1 #845 DRM 500 engine package 90 #226 Parts car Hit me up if you need anything. |
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#5 |
![]() Join Date: Jan 2021
Location: Beautiful Bavaria
Posts: 523
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Thanks, I will go through all those points.
I drove her rather hard recently, with coasting sections as well es full throttle accelerations north of 6k. But in general I drive my Z about 20-30 times a year only with an average of 50 miles per ride. And given my local roads the majority is relaxed back country road driving whereas I take care for WOT accelerations and secondaries engagement as often as possible. Secondaries operation is monitored by my secondary indicator lamp ![]() My guts say it's a sensor or something similar. Just not sure how much my guts know about LT5 engines...
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ZR-1 #638/1991 |
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#6 |
![]() Join Date: Oct 2012
Location: Germany
Posts: 228
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Measure out Matthias: the TPS signal must be at 0.50 volts at idle with the oem software on the memcal? Haibeck recommends 0.53 V with his chips. Other voltages can cause your problem.
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