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Discussion Starter · #1 ·
Hey everyone.
I Just bought a 86 camaro iroc z.the car runs good as long as your moving if you come to a light and take your foot off the gas it sometimes stalls out and when you start the car the rps jump back and fourth betweenn1000 and 1500rpms.also car burns rich u can smell the gas not being burnt off properly.and the engine light come on and says its electronic spark timing.
The car came withe a 305 tpi engine but was swaped for a 350 tpi but still has computor for a 305 tpi engine.also engine has had some mechanical up grades such as a cam,etc.
any suggestions as to waht will make the car run properly.everyobe one i talk too cant give me a sure answere.
thanks in advance
 

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First off if the engine was swapped to a 350 from a 305 it needs the computer and chip from a 350. There's alot of difference in calibration from 45 cubic inches of difference. Next question was the injectors bumped up to 350 injectors? How bout the knock sensor? If not the knock sensor will need replaced also with a unit for a 350. Last is the cam, the computer does not like when a bigger cam is added and the computer is not remapped to know the changes. If the cam is too big that alone is one problem. Telling us what size the cam is would be of help. As for idle, check the throttle body for slack by shaking it, once these get 150,000 miles on them they are worn out. Worn throttle plates cause vacuum leaks plus the throttle position sensor to read incorrectly. If the knock sensor for the 305 is in place this could be what's throwing the ignition code. The knock sensor works off frequencey. A 305 has a bore size of 3.736 and a 350 has a bore size of 4.000 inches, so when they knock they give off different frequencey's. If the factory sensor is still in use it could be causing it to retard to timing so much the car won't run. What is the number of the code it gives?
 

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Discussion Starter · #3 ·
Ya its a 350 with a 305 computor.i asked the guy who i bought the car fr he said he put a mild cam(not sure wht that means).and he did put bigger injecters and the throttle body is a large mouth holly throttle body.rockers with a 1.5 ratio(not sure what that means).car runs fine besides for the stalling at the light or going into drive or reverse.car has lots of power thats for sure.
so you think it needs to be chiped.and can a computor fr a 350 hook up to a wireing harness fr 305.and if it needs to be chiped i guess a performance engine shop could do that for me.
 

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First how about checking at a auto recycler, salvage yard, what ever you want to call it. See if they have an 1987 Camaro with a 350ci to get some of the parts doublevision suggested you change. I looked up 1986 Camaro on Advance Auto Parts.com it listed the 305ci as the only engine in 1986. So find a 1987 350ci. Knock sensor, throttle body position sensor, idle speed control sensor, computer (they just plug in), They are located behind the kick panel. Throttle body. Some computers require the dealer to flash them before they will work. I would do this before I took it to anybody. You could also buy a new knock sensor from the auto parts store for a 1987 Camaro. Then disconnect the negative battery cable for a couple of minutes to reset the computer. after re-installing battery cable check for all codes again. If all else fails you could get rid of the computer and install an intake and carburetor, coil, non computer controlled distributor to see if it runs better.
 

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Discussion Starter · #6 ·
Ya there is a 2800 stall converter in the trany now also a shift kit.so what your saying is with the after market cam you need a lower stall cobverter
 

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Discussion Starter · #7 ·
Sorry had to read it again.so i need a smaller camshaft.big job.would it help if i got a after market chip for thr car and get it tuned?
Or maybe replace the sensors and computors like cd minter59 said probly be better to start with the basic which are the sensors and go fr there
 

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Discussion Starter · #8 ·
The guy i got it fr said it was a mild cam,thats all i know.and i wouldnt know how or have the equitment to check the stuff your talking about
 

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Discussion Starter · #9 ·
So put back the original cam and injectors?
Is there anything i can do to fix the problem without taking the camshaft and injectors like adding or upgradeing other parts so it balances out?
 

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Discussion Starter · #11 ·
Ill get a vacume gage.
in the morning when i first start the car it bounces between 1000-1500rpm.at a light if it dont stall just below 1000rpms.
 
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