I have an 88 f150 with a 302. It always had a tick noise I’ve debated to be a ping or a manifold leak. I always leaned toward exhaust leak. Well today that was confirmed to be a ping. I accelerated through a turn in 3rd or OD, and it was slow since I was turning. It pinged so bad it sounded like a Cummins until it downshifted. What should I start with doing? I have already set the base timing a while ago. I thought it was set right, but maybe not. I’ll have someone double check it if I can plan a day with them to work on it. Probably towards the end of this month. But anyway where should I start with diag? I have always thought there was a small misfire at idle in drive. But I didn’t know what it was it started misfiring today in park to. Is compression something I need to start looking into? I haven’t replaced plug wires but I have done plugs and rotor/cap. And this is my daily, is it still okay to drive? I’ve never had it ping as bad as it just did. I run Costco 87 gas. I’m reading o2 sensor, knock sensor (do I have one?), run some sea foam through the intake. I would have to change the oil though if I did that. I ran fuel system cleaner through it with 1/4 tank, a while ago. I did notice the needle on temp gauge is slightly higher, but it goes back down. It was sitting over the right side of the N and usually it’s on the left. I was also seeing egg isn’t keeping cylinder temps down, and I’ll put a vacuum gauge on it and will update later this weekend what that says. Thanks for any info.

 

Make sure your #7 and #8 spark plugs wires are not running parallel at any point - crossfire was a problem on these motors. There was a TSB on it back in the day.

 

Spark Plug Wire Routing for '87-93 5.0L

ISSUE: Engine miss, spark knock, buck/jerk, surge and other driveability concerns may be caused by induction crossfire. This occurs because of improperly routed spark plug wires.

ACTION: If spark plug replacement is performed, the correct firing order and spark plug wire routing is essential to prevent the possibility of induction crossfire between cylinders. Refer to the following procedures for inspection of the spark plug wire routing and firing order. Properly reroute the spark plug wires if required.

Whenever a high-tension ignition wire is removed from a spark plug, the distributor cap, or the coil to perform a maintenance operation, Silicone Dielectric Compound must be applied to the boot before reconnection. Using a small clean screwdriver, apply a thin layer of Silicone Dielectric Compound on the entire interior surface of the boot. Do not apply compound to metal terminals.


FIRING ORDER

The firing order for 1987-1993 5.0Ls is 1-5-4-2-6-3-7-8. If #7 and #8, or #2 and #4 spark plug wires are routed next to each other at the separation bracket, an induction crossfire condition can occur.

To eliminate the possibility of the coil wire becoming disconnected, route the coil wire under the spark plug wires at the distributor cap.
(courtesy of Steve83)

 

The knock sensor is screwed into the top rear of the block. You may have to remove the plenum to gain access to it. It just might be the wires connecting to it are damaged.

 

There should be a code for the knock sensor if it malfunctions
Did you check the base timing with the spout out?
10 degrees
Is the octane plug there? Check the codes to see if it is gone
I believe 88's had them

 

Last time I pulled codes there was nothing and I’ve had this issue. I’ll pull codes again when I have a chance. I’m idling in park right now and after routing the wires the best I could with the brackets being different it still misfires. And in drive. I still hear the ping on the passenger side. Never had it on the drivers. How do I tell the difference between the ping and an exhaust leak. I want to make sure I’m not confusing them. It does it especially under load at low rpm. It does do it under load all the time though. The bracket for the wires is broken on the passenger side so I put 3 and 4 parallel, behind the egr tube. I put 1 and 2 on the front side, but the 1 is routed under the rest of the wires like a picture I had for it. The drivers side I just routed them like the picture the brackets just a loop that clips so I don’t have a way to keep them individually separated but I think they’ll stay in place decent I’ll check it later after driving. It sometimes pings at idle but you have to be under the hood to hear it
I will check the knock sensor, and I will figure out where the octane sensor is and check that.
I did do it 10 BTDC spout out

 

How do I check the egr valve? Something said to check that and if it sticks it will ping under load. I did a KOEO test and there were no current codes but I got code 33 in the continuous memory.

 

KOEO- 33 continuous memory
Koer-



Making some headway here, egr hasn’t had vacuum. I put the HVAC line on the EGR and it sounds like it has a cam now, and it tries to die.
Starting off, why doesn’t the line to the EGR have vacuum? Second what is the choppy cam like idle with the EGR hooked up saying?
KOEO and KOER- I also have a code 34- EGR control circuit fault with the egr having vacuum

 

That code will sure do it
Make it run like crap
The processor wants to see EGR flow and relies on the sensor to say it opened and closes
Your code 33 is saying the processor does not see EGR pintle valve movement.
Replace the EVP with a Ford one (after inspecting the valve)
There are pinpoint tests for that code 33 so you can verify the EVP failure or not
The EGR only gets vacuum when at part throttle cruise
It gets its vacuum from the EVR (EFR vacuum regulator) that is a solenoid controlled by the processor
You might have 2 problems and need a EVR too
Look up those pinpoint tests at your library or I can post in a day or 2

 

 

Thanks guys I’ll look into all of this

 

make sure that you have correct EGR,on truck, owners before you could have wrong one, exhaust leak/manifold crack, should have black soot around where its coming out.

 

I’m looking up the parts that I could possibly need, the EVP doesn’t look like motor craft makes it anymore I don’t see it I see the other brands. And the EGR valve same thing. And the same thing again with the EGR control switch.
I will get a loaner vacuum pump and see what’s going on with it, but I was just trying to find the parts so when I find one of them is bad I can go ahead and order it without searching.

 

Egr valve moves. I didn’t take the lines off of the EVR they are stuck. The EVR read 49.50 ohms. The EVP wasn’t reading any ohms no matter what I did. So that’s bad right? The EVP has 4.9v KOEO
How would the EVP cause pinging? Any other tests I need to perform? All I did was apply vacuum to the egr and test the resistance on the sensors. I am going to start it up in a second and check for vacuum to the EGR

 

Just drove it, and at temp if I give it throttle the egr won’t get vacuum so I need an EVP and EVR? Is the EVR supposed to give the EGR vacuum at 2-3k rpm in park that’s how I tested it. I didn’t see the tach so it may be a wrong estimate of what rpm I gave it but I gave it a good amount and nothing.
The EVR has 11.04 volts KOEO
If anyone could help me find the motor craft version of these that would be greatly appreciated, I only see the EVR with the last 2 digits being AA
Mine ends in a2a

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