The study reported in this article examined the impact of task type on the ways in which learners resolve grammatical language-related episodes (LREs) and whether the level of engagement affects subsequent language development. Data were collected over a six-week period. Thirty-two Iranian second language (L2) learners were paired up to complete a text editing task and a narrative writing task. In order to detect grammatical LREs, all collaborative dialogues were audio-recorded and transcribed verbatim. The LREs were classified into cognitive conflict episodes (CCEs) and non-cognitive conflict episodes (non-CCEs) based on the extent to which pair members deliberated over the target forms and challenged one another's contributions. The results indicated that the text editing task led to a larger number of CCEs than did the narrative writing task. Moreover, more grammatical CCEs were correctly resolved in the text editing task than in the narrative writing task. In addition, while learners resolved high percentages of the CCEs for both tasks, they could correctly resolve only half of the non-CCEs for these tasks. Finally, learners' scores on the immediate and delayed posttests showed that the text editing task was more conducive to both short- and long-term learning of grammar.