EA82 missing at acceleration from idle

[jimkup]

My EA82, SPFI, MT, having problems when just starting to accelerate. She kinda misses unless I rev her up a bit before releasing the clutch. She seems to idle ok & once she gets up to speed she seems to run fine. Also, my mpg is better lately than it has been in years, about 30 mpg. I have changed all the usual stuff, disty cap & rotor,NGK Plugs, fuel & air filter, has 8mm solid core wires & a high performance Accel coil. Has been gradually getting worse so I bought a compression tester & all cylinders were right at 157psi except #1 which was at 100psi. That side of the engine (passenger side) also has a pretty severe tick & some time back I replaced two lifters @ the #3 cylinder. So my question is: Would this problem be caused by a problem with the cylinder head...ie valves, springs, or guides? While i had the compression tester hooked up I let it sit for a while & pressure stayed at 100 psi. Also, would a rework of the head (valve job, new guides, & resurface) resovle the low compression issue or could it possibly be deeper inside the block, like maybe rings? Engine doesn't hardly smoke & uses very little oil between changes. Any other items or ideas I should try or check while the cylinder head is off? Thanks in advance for any input or advice!

[555Ron]

Probably the first thing to consider would be a head gasket.

 

Check for water in your oil... oil in your radiator.

[jimkup]

Probably the first thing to consider would be a head gasket.

 

Yea, obviously I will install a new head gasket upon reassembly, but are you thinking that maybe the Gasket had some compression blowby?

[jimkup]

Yea, obviously I will install a new head gasket upon reassembly, but are you thinking that maybe the Gasket had some compression blowby?

ok all here is the latest update for my issue. Took the passenger side head to the head Shop for rebuild. After they bead blasted the thing & removed the valves they found not only the typical surface cracks between the valves but the crack between the valves on the #1 cylinder went way down inside the ports & it was obvious that I was loosing compression due to the carbon & soot around the cracked area. Also, the valve seals on the two valves had come out of the seats and were moving up & down with the valves. Result - Head Trash!

Luckily, sometime back I purchased a used set of heads from a USMB'er & took them over to the shop. They removed the valves & blasted the area between the valves & even though they were cracked, it was not near as bad as what I had. So, they are in the process of rebuilding the head for me & hopefully I will get it back & installed without any other problems & good compression. BTW - the old head gasket was still in decent shape - no obvious areas of leakage. Was about 10 years old. I will try & post pics of the old cracked head. I am surprised the darn thing didn't break in half 'cuz the crack is so big & deep inside the head.

[jimkup]

ok all here is the latest update for my issue. Took the passenger side head to the head Shop for rebuild. After they bead blasted the thing & removed the valves they found not only the typical surface cracks between the valves but the crack between the valves on the #1 cylinder went way down inside the ports & it was obvious that I was loosing compression due to the carbon & soot around the cracked area. Also, the valve seals on the two valves had come out of the seats and were moving up & down with the valves. Result - Head Trash!

Luckily, sometime back I purchased a used set of heads from a USMB'er & took them over to the shop. They removed the valves & blasted the area between the valves & even though they were cracked, it was not near as bad as what I had. So, they are in the process of rebuilding the head for me & hopefully I will get it back & installed without any other problems & good compression. BTW - the old head gasket was still in decent shape - no obvious areas of leakage. Was about 10 years old. I will try & post pics of the old cracked head. I am surprised the darn thing didn't break in half 'cuz the crack is so big & deep inside the head.

 

Ok, got the head back & installed ok. Afterwards, I had a slight amount of additional power, but still the bogging down or missing while accelerating, especially under a load. Waited til it got real dark & checked under the hood for sparking. None found. Decided to install new disty cap & rotor. As I was pulling wires & generally looking around the area I noticed the coil wire at the coil had some fluid in it. Upon further inspection, found that the Accel SuperStock Oil filled Coil I installed about a year ago had been leaking. When I started looking really close, I found oiley residue all around the coil & mounting area. The coil mounts horizontally but there was no crack or anything obvious that would cause the leakage. I had oil all on the power transistor and electrical connectors and wires in that area. I took everything apart & cleaned & dried & cleaned corrosion from ring connectors (that go to coil) with wire brush and installed the original coil back on the car. Afterwards, no missing, bucking, or bogging down at all. So, at least for now, she is purring like a lil' kitty & has noticeably more power! Moral(s) of the story:

1) don't waste your money on the oil filled coil.

2) keep wires and connectors for the igintion system clean & dry.

[MilesFox]

have you pulled the engine codes? maybe the TPS is bad

 

my car sometimes bogs a little at low rpm upon acceleration. my ecs stays on code 32 o2 sensor. i conneced a grond to the exhaust, the car would run good and the ecs light still on. then the ecs light goes off, i can feel a difference in the way she pulls and the smell of the exhaust. but every now and the n the ecs light returns and the car bogs out again

 

it hasnt been so bad lately, no code pulling this time. maybe its off just enought o affect how it runs but not throw a code

 

my exhaust is not hung on the mount below the tranny, i have read about the o2 sensor grounds thru the exhaust(and not the exhaust stud on the head) and adding a ground wire seems to be helping, although it took the car 200 miles to notice it

 

if i have any more problems my next move would be throttle pos sensorn related, my car is an 88 sedan with a motor from an 86 wagon and the spfi intake form a 91 loyale

[jimkup]

have you pulled the engine codes? maybe the TPS is bad

 

my car sometimes bogs a little at low rpm upon acceleration. my ecs stays on code 32 o2 sensor. i conneced a grond to the exhaust, the car would run good and the ecs light still on. then the ecs light goes off, i can feel a difference in the way she pulls and the smell of the exhaust. but every now and the n the ecs light returns and the car bogs out again

 

it hasnt been so bad lately, no code pulling this time. maybe its off just enought o affect how it runs but not throw a code

 

my exhaust is not hung on the mount below the tranny, i have read about the o2 sensor grounds thru the exhaust(and not the exhaust stud on the head) and adding a ground wire seems to be helping, although it took the car 200 miles to notice it

 

 

 

if i have any more problems my next move would be throttle pos sensorn related, my car is an 88 sedan with a motor from an 86 wagon and the spfi intake form a 91 loyale

 

No, haven't pulled any codes. Every now & then the "check engine"? light comes on when I start the engine, but always goes off after a minute or two of driving.

 

I did notice the other day after I replaced the head & thought I had all connectors hooked back up & fired her off, that the TPS Connector was not connected. I had forgotten to hook it back up, but it still started & sounded ok. When I noticed the connector was not connected, the check engine light was on & after I turned it off & reconnected the TPS Connector, the check engine light went out.