It all started 3 weeks ago when I blew a head gasket. I tore it down and rebuilt it. I had the heads inspected at a machine shop pressure tested and resurfaced. During rebuild I replaced thermostat, water pump, spark plugs, wires, and cap and rotor. Once finished I changed the oil and flushed the cooling system. Fired it up and set the timing everything sounded good. No knocking, no missing, no chattering. I figured I was good to go. Try takin it for a test drive and get out of the drive way and there is absolutly no low end torque. It was shifting very hard and jumping gears. The engine sounded good but power was not being transfered. Took it back and noticed it was running about 220 F. I also noticed it filled the overflow compartment. I checked the basics like wires spark fuel pressure, loose vacum lines. Found nothing. I check mass air flow sensor and clean it and nothing improves. Later that night the engine started missing. I took a look at the wires and noticed one of the was fried. I replace it then try again. Engine idles about 500 RPM lower than before the rebuild. For some reason my exhaust is running outrageously hot. Any wire within inch and half will fry. I pulled the spark plugs and noticed a couple of them were wet with gas. What would cause the engine to run lean? I've tried everything I can think of anyone have any ideas?

5.7 350
89 Firebird GTA
TPI

 

what makes u think the engine is running lean if the spark plugs are wet. u might be running a bit rich and that could cause the unburned fuel to ignite in the exhaust causing it to become very hot. i've seen headers glowing red from that problem. check to make sure tour alternator is charging properly that could cause a miss being low on power.hope this helps good luck

 

possible unhooked vacume line to the fuel pressure regulator?

 

Ever find out why the original problem occured? Chevy motors don't have a habit of blowin head gaskets.

 

High water temps after head gasket problems point to bigger trouble. I have done this in the past to 'test' the block and heads for the unmentionable. Remove upper rad hose and thermostat housing and thermostat. Leave water in block filled to top of thermostat hole in intake. Now remove all the spark plugs pressurize the cylinders one at a time like you were doing a leak down test, valves closed. Watch for air bubbles in the water at thermostat housing. Pray for none.

 

sorry i miss posted I meant the are running rich and not lean. As for knowing the cause of the blown head gasket in the first place I was hoping it was just wear and tear. The engine has 100K. Before this all happend I also was getting a little blueish white smoke out the exhaust just on startup. I had my valves and seals check and were fine. Could a blowing head gasket cause similar effects. As for the altinator it is about 1 year old and when everything is running there is no miss until the engine gets hot enough to burn one of the wires. So I think I can rule that out. As for trying to pressurize the cylinders I will tackle that tomarrow. If I do see bubbles what does that mean? Where is the fuel pressure regulator located? Is there any way to test it? About the hard shifting and jumping of gears I had someone tell me to adjust the connection that goes from the throttle body to the transmission. When doing this breakdown and rebuild I never took off the plenum and set it off to the side. He thinks I might have pulled it and cause it to shift incorrectly. Is this true? Does anyone know how to adjust it properly? Thanks in advance!

 

I will assume (notice the first three letters in that word) you are running a 700R4 trans. If this is true the cable going to it from the throttle body has a VERY CRITICAL adjustment! If it is not correct you will burn up that trans quickly.
What I have seen happen is that the cable gets connected to the wrong spot on the throttle body after an R&R, which causes problems. Also the adjustment on this cable should have a button to push that allows the cable housing to slide through the mount. If this button was pushed at any time the adjustment is probably wrong.
If you blow bubbles in the water jacket from the cylinder it has a leak, pressure from the cylinder should not go into the water jacket ever! Check all cylinders but especially the one you had problems with eariler, if you know that the heads were placed back in the same place.

 

One more thing on the pressure test of cylinders. Make sure the valves are closed, this will require valve cover removal to look at rockers, sometimes it is hard to keep the piston at TDC (where both valves are closed) engine will want to turn over when air is put into cylinder. You have to get the crank in just the right position so it doesn't rotate. I have had to loosen the rocker arms to the point that they do not open the valves which allows you to pressurize without consideration to crank position.
This pressure will also serve to tell you how good the rings and valves have sealed the cylinder. Check it out, you can hear the air coming out the intake or tailpipe or crankcase.
I usually use about 80-100 psi to test.

 

Here's a stupid idea..

when you set the timing, you unhooked the tan wire for the timing right? Did you hook it back up?

 

Yes I do have a 700R4. The question is would that need adjustment if I never removed the cable from the plenum? The guy I talked to thought I might have pulled the cable when setting the plenum off to the side. Would this be possible. I picked up a compression tester today so I am going to check it out and see what the results are. As for the timing yes I did unhook during setting and rehooked once completed. Does anyone know if there is any way to test the Fuel Pressure Regulator without haveing a vacume tester? Also where is the located? I am not familiar with it. Thanks in advance.

 

Are you sure you have the valve timing correct? One tooth off would sure cause problems...

 

What is valve timing? If it has to do anything with the dissassembly of the head the machine shop did it and rebuilt it. Otherwise how do I check or troubleshoot it?

 

Cam gear to crank gear via timing chain determines valve timing...
I can surely see a senario of low/no torque if you were off a tooth when you reassembled the engine. Its happened before for sure..
A compression test would likely show it...A leakdown test definitely would.

 

I tested the ohms on the injectors and got these results
Clyinder
1- 16.4
2- 15.6
3- 12.5
4- 12.4
5- 12.7
6- 12.5
7- 16.4
8- 16.3

I also pulled the mass air flow sensor connector off and started the car and idled alot better than with it connected. There was no error codes with it connected but could this possible be the cause of the cylinders running rich?

 

More troubleshooting today. I hooked up a fuel pressure gauge and was geting 40 psi in run and started position. Although when key is off it leaked down to less than 20 PSI. I pulled the injectors and pressurized the pump and found no leaking injectors. I picked up a fuel pressure regulator and are going to install it tomarrow. I also hooked up a vacume tester and it ran pretty steady at 30 psi. Any more suggestions. Running out of ideas.

 

You are pulling 30 on your vacuum gauge???? Better check that again!
What were the results of the cylinder pressure/leak down check?
How fast does the fuel pressure bleed down from 40 psi to 20 when the pump is turned off?

 

I havent done the pressure test on the cylinders yet. And took a while to bleed down. Slow leak but steady. I thought thats what the vacume gauge said what is normal for vacume?

 

Fuel pressure: After pump runs and pressure reaches 43 psi or so turn off pump watch gauge, should be no leakage for 5-10 mins. if you pass that call it good. It could lose a couple lbs. just after pump turns off, that would be O.K. but after that a steady gauge reading is a must. If it bleeds down find the return hose to the tank and pinch it off. If the bleed down stops, bad regulator, if it keeps going down, injector. Which you said you checked already.
Vacuum reading: If you are running a stock cam, I would look for around 17-20 inches of vacuum at idle. If you have 30, either your gauge is off or that engine is some kinda sucker!

 

After further investigating on the fuel pressure situation I found that I have some leaking injectors. The wierd part about it I pulled the fuel rail and pressurized the fuel pump and I saw nothing for leakage. Then I pulled the injectors and did the cheap cleaning method with rubber tube brake kleen and a intermittent 12v source to find 4 injectors just leaking bad. 2 Injectors hissing small amount. 2 Injectors not leaking at all. What are the chances of all those starting problems when I never had a problem before this occurance? Question concerning fuel pressure regulator, do you need a special star bit in order to take the cap off to get access to the regulator itself? Thanks in advance.

 

Injectors can be cleaned and tested for $12 ea. using ultrasound and a flow bench. I believe the place is rich@crusinperformance, I can check that if need be. They will also match flow a set for an extra fee.
Yes a special torq bit is required, I believe any auto parts store with Lesile tools will have it. Or you can take them out with pliers, which destroys them, and replace them with normal screws/bolts.
Injectors must be leak free and have proper spray pattern for engine to operate properly. No amount of "tuning" will overcome this problem.

 

You have 4 injectors that are pulling more than 1 amp.
With 12 volts an injector should pull about 0.7 amps (12v/16.5 ohms=0.7272 amps.)
I wouldn't use a 12v source to test an injector, the coil can be damaged if the voltage isn't switched fast enough, 2ms - which I doubt is humanly possible.
Did you number the injectors? can you match them to the ohms list?

 

Yes I did label them. Even if I did burn out the coil in the injector I was planning on replacing all 8 with new sense more than half were leaking. I am sure I was not the cause of all because 3 of the 6 leaking was allowing fluid to pass through without even touching a voltage source. I am just hoping this is the complete cause of my problems. Does anyone know how to exactly adjust the cable that runs from the throttle body to the transmission? Thanks in advance.

 

Going back to your original post and reading over the symptoms, it sounds like to me that the engine is running good--right? If it's not going anywhere and shifting eratic, basic trouble shooting says it's a tranny problem. Since it was working good before rebuild, IIT sounds like it has to be the tranny cable or adjustment or something along those lines. U may need to take it by a tranny shop, explain what happened, what the symptoms ae and let them take a look.

 

Push the button on the cable, should be "d" shaped and located right behind the mount bracket on drivers side front of plenum. While pushing the button, slide the outer housing back towards the trans., release the button. Now with your hand open the throttle body WOT, this should pull the outer housing thru the adjuster, thats it, adjusted.
One more thing, have someone step all the way down on the 'go' pedal while you watch the TB, does it go as far as it did when you moved it by hand? Alot of gas pedals do not make the throttle body go all the way to WOT! If yours is one of them you need to address this.
On the injector cleaning, the place to send them is cruzinperformance, do a search on the net and it will come up. The problems you mention on the leakage could be they need a good cleaning, but the ohm readings on some of those appear to be out of tolerance, which would have to be replaced.

 

I used cruzinperformance--I WAS IMPRESSED (and I am pretty picky and not easily impressed!!!) This guy is definately into customer service!!! He spent time on the phone with me and at NO point did I ever get the feeling he was wanting to get off the phone. He has an excellent reputation and now I understand why. He posts test results of your injectors, on his web site, before and after on some charts and graphs--sends U a password for U to log on to your info. Well worth it!