I was driving my car last Thursday and had the L shaped coolant hose at the back of the firewall split about a 4 inch length and start spraying coolant. I had no idea what had happened when it occurred, I only saw a small puff of white behind me, and didn't know what was going on. No smell, nothing. So, I took the car the trip home of about 3 miles, and by the time I parked it I glanced at the temp gauge and it was about 2-3 tick marks below the red area. I popped the hood to see that the hose had split, and had sprayed coolant virtually everywhere. Now, fast fore ward to tonight. I finally got the car back together after replacing the hose and doing the required torque check of my ARP head studs after a few heat cycles. I took the car out for a drive and had a severe misfire under any sort of load. I then took the car back home and removed the plug boots to discover that coolant had gotten into the rear 2 plug holes reasonably badly. I sucked the coolant out of all the plug holes and removed all the plugs. They all had faint white markings on the ground straps, but the rear 2 had pretty severe white clean markings on the ground straps. I believe that is a sign of coolant being burned if I remember correctly. I also turned the engine over with the FI fuse removed to push any coolant or crud out of the cylinders that may of gotten in when removing the plugs. I installed new plugs and put everything back together and took the car for another drive. It drives great until I get it into boost. It then has a slight to mild misfire on medium to hard acceleration. Any suggestions on what it may be? I don't believe I blew the head gasket with the metal gasket and ARP studs, at least I hope not.
Help needed. Misfire under boost after coolant hose incident
- Thread starter SupraMan1987
- Start date
Did you check to see if colant on where the spark plugs are? Under the cover. There have been a couple of times it's gotten wet and had to be dried out.
I did, and their was. Sucked it all out that I could get with a turkey baster. Should I take my heat gun on low and attempt to dry it out more?
grab an air blower and blow it out that way. Re check your plugs, check the gap, and make sure you do not have any carbon tracking already. your boots may have been damaged by the coolant, causing them to mis under excessive load
I replaced the plugs already and gapped them .030. Are you saying to gap them again? Also, should I blow out just the plug holes and the plug boots where they attach to the plugs, or anywhere else? Also, what is the tell tale sign of carbon tracking? It's been a long time since I've messed with any misfire stuff like this.
89supra7mgte;1459855 said:
+1, blow out the spark plug boots, scuff the plugs a little to remove the white chaulky stuff, then try again. thats only if you dont have access to an air compressor, compression/leakdown tester, or a coolant pressure tester. if you dont have any of the 3 things, then all you can really do is read the plugs after a few pulls. possible coolant might have made its way into the afm and other connectors?
if it were me id do a leakdown test on each cyl at tdc and look for air bubbles in the coolant. worst case scenario, you warped the head. best case scenario you got fluid in the electrical system. let us know your findings
What brand/model plug and where did you set the gap? Did you test the plug wires for TSRM resistance spec? Inspect the coil packs for any cracks.
In most cases the "white chalky stuff" is due to weak connection to the plugs, in my experience anyways, would need to visually see if its the same. the weak or bad connection causes the spark to track out wherever it can. carbon tracking on a plug will be distinct black lines on plug itself. pull the plugs and compare the markings on the boots and plug see if they are there. And to note after cleaning everything out that was contaminated with coolant use di-electric grease on connectors and plug boots. this will soak up rest of moisture and create a good corrosion resistant contact.