So I want to hash out the tail of the past year from the beginning to get feedback on where you all think I should go next. I have learned a lot about this truck and this engine but I'm lost as to what is happening in my engine that is causing the problem. Thanks for all the help thus far! Big shout out to @GLTHFJ60 for laying on the ground with me and teaching me the ropes!
Bought a 91 one year ago. Very little issues really just a almost complete brake rebuild, replace a leaking gas tank and filler neck and seal up a leaking sunroof!
Has far as the engine....super black oil, changed it and turned super black again within a week. So I changed it again! But it ran fine, seemed to have some power and no knocking, but the exhaust system was completely busted and providing no back pressure. First repair therefore was the exhaust, complete rebuild from the headers back. Highflows were already in place, not clogged and worked back from there with lots of increased flow with dual pipes. Shortly after this repair, we determined there was a knock in the engine, and never really saw a power gain after the repair. Finally got around to a valve adjustment and it drove great, tons of horsepower gain, it was like a new truck! The very next day oil galley plug blows out but in the driveway so I was able to catch it. This was my first repair flying solo and with some help went very well. Set screws are holding nicely (see pictures). The next time I started it up, I went to the shop to change the oil and filled it back up with the usual 10-40 with some MARVEL mystery to start loosening up all the gunk we found when doing the valve adjustment, then went to fill it up with some 93 (which I had been using to eliminate the knock) and pulling out of the station (only about 20 miles since the oil change) all the power gains from the valve adjustment went bye bye. Within another 20 minutes the engine light starts coming on whenever I accelerate and stays on for a few moments then cuts off. That night I take the battery off to reset the system and codes. Restart in the morning, first acceleration and engine light comes back on! Light pretty much stays on. Dealer pulls codes and says O2 sensor (weren't sure which) and some weird code about speed. No one had a clue, so they accidentally replace the speedo cable which had broken at some point, and say lets go back and do another valve adjustment. So Bob who has been at Fred Anderson for 25 years gives me my second valve adjustment in some 55 miles. They return it back to me yesterday and it runs amazing. All the power gains I had achieved in the first adjustment I got back! Problem solved, Bob found 4 valves were too tight. But the next day (today) I start it back up and the power is gone again!!! Super sluggish, almost no throttle response, slowly put it to the floor and the rpm gauge doesn't even move. But this time no engine light. So I drive 20 miles and stop, pull the circuit breakers for the electronic fuel injection system, wait the 15 mins. SOME power comes back for about 10 miles but more or less back to the slow stubborn unresponsive goat syndrome. Then I put a tank of 87 in there to see if the valve adjustment fixed the knock, and nope, knock is still there but not quite as bad. AT THIS POINT IM
LIKE WHERE IS THE FOR SALE SIGN!!
And in the garage she will sit again until I have a chance to go at it....
Thoughts?!?!
Bought a 91 one year ago. Very little issues really just a almost complete brake rebuild, replace a leaking gas tank and filler neck and seal up a leaking sunroof!
Has far as the engine....super black oil, changed it and turned super black again within a week. So I changed it again! But it ran fine, seemed to have some power and no knocking, but the exhaust system was completely busted and providing no back pressure. First repair therefore was the exhaust, complete rebuild from the headers back. Highflows were already in place, not clogged and worked back from there with lots of increased flow with dual pipes. Shortly after this repair, we determined there was a knock in the engine, and never really saw a power gain after the repair. Finally got around to a valve adjustment and it drove great, tons of horsepower gain, it was like a new truck! The very next day oil galley plug blows out but in the driveway so I was able to catch it. This was my first repair flying solo and with some help went very well. Set screws are holding nicely (see pictures). The next time I started it up, I went to the shop to change the oil and filled it back up with the usual 10-40 with some MARVEL mystery to start loosening up all the gunk we found when doing the valve adjustment, then went to fill it up with some 93 (which I had been using to eliminate the knock) and pulling out of the station (only about 20 miles since the oil change) all the power gains from the valve adjustment went bye bye. Within another 20 minutes the engine light starts coming on whenever I accelerate and stays on for a few moments then cuts off. That night I take the battery off to reset the system and codes. Restart in the morning, first acceleration and engine light comes back on! Light pretty much stays on. Dealer pulls codes and says O2 sensor (weren't sure which) and some weird code about speed. No one had a clue, so they accidentally replace the speedo cable which had broken at some point, and say lets go back and do another valve adjustment. So Bob who has been at Fred Anderson for 25 years gives me my second valve adjustment in some 55 miles. They return it back to me yesterday and it runs amazing. All the power gains I had achieved in the first adjustment I got back! Problem solved, Bob found 4 valves were too tight. But the next day (today) I start it back up and the power is gone again!!! Super sluggish, almost no throttle response, slowly put it to the floor and the rpm gauge doesn't even move. But this time no engine light. So I drive 20 miles and stop, pull the circuit breakers for the electronic fuel injection system, wait the 15 mins. SOME power comes back for about 10 miles but more or less back to the slow stubborn unresponsive goat syndrome. Then I put a tank of 87 in there to see if the valve adjustment fixed the knock, and nope, knock is still there but not quite as bad. AT THIS POINT IM
And in the garage she will sit again until I have a chance to go at it....
Thoughts?!?!