Won't rev up

General chat about the car goes in here.
zachmac
Posts: 1278
Joined: Sun Aug 24, 2008 9:20 am
Your car is a: 1978 Spider [1979 2 ltr engine]
Location: Aiken, SC

Re: Won't rev up

Post by zachmac »

+1 on the coolant tee temp sensor as a possible issue.
Jeff Klein, Aiken, SC
1980 FI Spider, Veridian with Tan (sold about a year ago), in the market for another project
1989 Spider, sold
2008 Mercedes SL65
2008 S600 Mercedes V12
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spidernut
Posts: 1906
Joined: Wed Jan 25, 2006 12:20 am
Your car is a: 1979 Fiat Spider Automatic
Location: Lincoln, CA

Re: Won't rev up

Post by spidernut »

Here are some things that should be checked.

1. Timing belt orientation: Triple check the orientation of the crank pulley to the cam pulleys and aux shaft pulley to ensure the timing belt is installed properly. Typically, if one of them is off the motor will backfire through the carb and/or exhaust. It will run like crap too.

2. Ignition timing: Make sure it is set to the proper distributor timing at idle. Double check the magnetic pickup gap. If it is too large or too small, it can cause problems.

3. Spark: Check the coil output (see the videos on this page: https://sacramentoareafiats.weebly.com/ ... dvice.html for a former International Auto tutorial on checking the coil output.

4. Ignition control module: I don't personally know how to test it, but they are a cheap replacement

5. Engine ground: Make sure your engine is grounded properly to the chassis. Often times the ground cable is deteriorated or is no longer connected a clean spot on the chassis.

6. Fuel pressure: Double check the fuel pressure using a pressure gauge connected at the EFI or carb at various RPMs.

7. Spark plugs and wires: Make sure resistance on the plug wires is within spec, and make sure plugs are in good condition.

8. Check compression dry and wet. Conduct a compression leak-down test.

9. Since you have EFI, make sure that the coolant temp sending unit on the coolant T is connected properly

Then report back.
John G.
1979 Spider (Owned since 2000)
1971 124 Sport Spider (Owned since 2017)
1977 Spider (Sold 2017)
1979 Spider (Disposed of in 2017)
1979 Spider (Sold 2015)
1980 Spider (Sold in 2013)
1981 Spider (Sold in 1985)
2017 Spider (Owned since 2019)
herman
Posts: 17
Joined: Fri Jun 16, 2017 7:42 am
Your car is a: 1974 spyder

Re: Won't rev up plan "B"

Post by herman »

I would like to start by thanking everybody for their help my mechanic tells me he tried everything even brought his father in out of retirement who installed the first engine. The two of them tried the timing all good fuel injectors all good, didn't have much of a choice pull the engine and open it up or find a another engine. I guess the fiat gods where looking down on me I remember of a spyder in the area went to the door and asked if the car was for sale lucky me the owner was thinking of scraping it the body was in bad shape the roof was gone but the engine looked good had 69,000 miles on it made a great deal we switched engines all is good in fiat land again both my mechanic and is father want to look deeper into the other engine I'll let you know what they find again thank you all for your help. Herman
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spidernut
Posts: 1906
Joined: Wed Jan 25, 2006 12:20 am
Your car is a: 1979 Fiat Spider Automatic
Location: Lincoln, CA

Re: Won't rev up

Post by spidernut »

I will be very interested in hearing what they have to say.
John G.
1979 Spider (Owned since 2000)
1971 124 Sport Spider (Owned since 2017)
1977 Spider (Sold 2017)
1979 Spider (Disposed of in 2017)
1979 Spider (Sold 2015)
1980 Spider (Sold in 2013)
1981 Spider (Sold in 1985)
2017 Spider (Owned since 2019)
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